The sub-genres of historical games are those that cover historical and known periods and events, and then sets up a framework that represents what actually happened. Everything from economic factors to societal factors, plus technology and its changes are all ripe for game mechanics in any historical game. The majority of these games tend to fall in the Grand Strategy to Tactical simulation types of games, and these date back all the way to chess and was more regularized and modernized during the Napoleonic era. Chess gives weight and movement ability to units based on social, religious, and military capacity, which makes for an interplay between those pieces on the board as representing how a ruler might attempt to maneuver the pieces of society and the military to gain victory over a foe. It is a primitive sort of game, to be sure, as it doesn't vary pieces by culture, economy or technology, but then it isn't supposed to be representing an actual conflict in fact but one of extrapolation where these matters are considered to be roughly equal. History, and regimes, are not so easily described and the varieties of peoples, religions, societies, economic practices and technology across the entire sweep of these things all help to define a game when it is set in a definite era or time frame.
A game like Third Reich from Avalon Hill described the immediate time of when World War II started and constrained it to the European, Western Russian and North African strategic theaters of war. Nations had units that were built with Basic Resource Points (BRP) and any savings in those at the end of the year saw a portion of them going to grow the economy. Any conquests of nations with BRPs also added to that economic total for the entire Nation, though didn't grow the economy. Victory was achieved by taking a number of strategic cities or other locations, and that would determine the game's end. The United States was an off-map power that would become available to the Allies when it declared war on Japan, another power not represented in the game. Each player got to determine what to build each quarter, with some units, like ships or strategic units (submarines and ASW units) playing a part in BRP supply for the UK. As this is a top-level game and personalities are not considered, the premise is that certain historical actions will happen , though there are some random alternatives that can influence the game but only at the start of the game. The mechanics are set and relatively static, but the disposition of economic output is up to the players. Gaining a nominal victory is difficult for either the Axis or Allies, though there are some benefits to the Axis early in the game which shifts due to economic factors to the Allies as the game unfolds. It is possible to not declare certain wars, to declare wars on other powers, or seek to get an agreement with some powers if certain conditions are met. Any start of the game depends on the skill of the players involved and history then revolves around the decisions made with the known game mechanics for movement. An Allied victory isn't guaranteed even with the slight shifts in resources that amount to quite a bit in the latter stages of the game.
A more modern game, like Crusader Kings II by Paradox Design Studios, spans the early Medieval from just before the rise of the Vikings all the way out to approximately 1500. That isn't to say that religious conflict didn't continue, as it did, but that the mechanics for that need to shift given the changes to societies and technology across the known world and take the New World into account. CK2 is a dynasty centered game, and the player has a bloodline to protect and one that he or she will pass over to their heirs. As such it has an important social dynamic that reflects the era, even when it has elements that aren't represented in a decent fashion, historically. Wealth, prestige, piety, buildings, units and technology are all present, even if having a major amount of hand-waving at them for play balance. Thus playing a CK2 campaign is an exercise in alternate history with the dynamics represented ones that were important to that 8th to 15th century world. Are there elements left out, badly represented or downplayed in the game? Of course there are! Gavelkind inheritance was NOT the standard for that era outside of a few counties in Kent and Wales, so it is a bad conception of how to hand over power across generations that is aimed at game mechanics, not history. The Holy Roman Empire was divided during the early years of Charlemagn's rule among his sons who had Kindoms under the Empire. Thus the Empire, itself, was set for being fractured, even if one of his sons got the Imperial nod, the other Kingdoms had already been set up under that larger banner. All members of that dynasty in the following generation got a claim to being a legitimate holder of the HRE, and that would pass down and cause major problems and see the HRE decline. This was not Gavelkind in any way, shape or form, but the actual ruler creating a way to ensure that the dynasty would continue, even if it also set them at each other's throats after he died. Of course if you take up that role, then you can try and change the dynastic situation, alter the line-up, and maybe do a few choice assassinations. History isn't set in CK2, although the rulers do, typically, have things they want to do: Nations or rulers have no perpetual friends, but they do have perpetual interests. CK2 replicates that pretty well given the constraints of the game.
The Strategy and Grand Strategy games are the main venue for historical work, though the concepts of 'theater of war' would only slowly evolve as Nations grew in power and reach so that there could be separate 'fronts' and theaters. Those concepts grew out of those first put down by Rome, Persia, Greece and other Nations, in which fighting one foe in one area might invite an attack from a different foe from another direction. This caused a split in manpower allocation, resources, and would bring these ideas of 'front' and theater into being. From simple single instances of two-front wars there would come a time of multi-threat wars that required more than one simple venue for practice. Different games offer different dynamics for this. The larger the scope, to the point where armies are a form of influence, could be seen in the game Diplomacy by Avalon Hill. At he largest scale the pre-WWI game represented the attempt to spread national and imperial influence on a global scale. Diplomacy as a game was a highly abstract one that was a first solid attempt to move the Grand Strategy game to a much higher level of representation to both simplify game play and yet leave complexities of how one supported influence abroad. This concept would later be expanded by the game designer Greg Costikyan and Pax Brittanica, a game that still featured influence and diplomacy, but also represented much of the pre-WWI ethos and the rising tide of diplomatic and military spheres that would serve as the pressure for the Great War. Players have to be aware of global tensions as their actions and activities can push the world and its Empires slowly into that fateful showdown. A minor conflict in a far-off land may not seem like much, but if the tensions are already high then that might be enough to tip the balance. Trying to defuse situations requires diplomacy among the players, to the point of actually making their own treaties and then deciding if they will abide by them. By giving so much free-play to players, the ability to come into a dominant position before the Great War is a matter of skill, intrigue, military deployment and then seeing if enough of the influence of one's own Empire is enough to be in the predominant position when the Great War comes. Britain is in the supreme position in this game from the start, and can simply lay basic claims to the entire world and not have to do much of anything else. As such it is an easy to play Empire for novice players, while experienced players take on the role of 'Who will be in Second Place?' which is viable for all the major and minor Empires available in the game.
Game dynamics must represent the era being presented in some form, be it economic, political, diplomatic, dynastic, military or even personal. Factions are a standard part of game play for most Strategy based games, though they can just be the Nation or Empires involved but can go all the way down to the family level. Factions inside larger organizations are also a viable dynamic, thus in CK2 there can be factions seeking their own ends inside a Kingdom or Empire, and those might not necessarily by related to dynasty or might involved other dynamics between other dynasties that the player may not catch on to early on. In Pax Brittanica there are no interior factions, but the ever climbing world threat meter which encourages circumspect use of force for only those things that truly matter. These game dynamics represent certain aspects of the real world that were present, even if those who knew about them didn't understand what they were leading to. In Europe, leading up to WWI, there was no understanding how the technology had changed the use of troops and their deployment. Yet the Battle of Richmond which did have military observers from Europe saw what had happened there: trench warfare due to the high accuracy of rifles that could be reloaded very quickly. The Gatling Gun was not understood as anything other than a form of artillery, even after Maxim had introduced his machine gun to the European powers. The trench warfare in the US Civil War would be the way of the future when all sides had such technology to use. Pax Brittanica assumes this continued leveling of technology as a 'given', and can't be influenced and, truthfully, wouldn't change the slow move into WWI.
Any time a player puts themselves in charge of a group, government, nation or military in a historical setting a new take on history begins. One person with a slightly varied background or even the same background as witnessed in history is not a guarantee for history to replay itself. That is true of any era so long as the AI for the other individuals is up to the task of simulating those goals and directives held by those who were in historical positions. Yet battles can be determined not just by numbers of troops but by the quality of those leading them and the technology they deploy. To get to mounted Knights in Europe requires the invention of the stirrup which allows for the transfer of shock to a horse from an individual mounted on it. Without that a man on horseback could be a wonderful archer and might even do a bit of slashing with a sword or saber passing lightly armored troops, but the ability to concentrate the momentum and force of the horse and man via a lance is impossible, or at least impossible to stay mounted thereafter.
While an ancient invention, it took time to understand the actual utility of it in mounted warfare, which meant that armored soldiers on horseback with lances was a late term development as all the rest of that had to be discovered as well. Once properly mounted and trained, a Knight on horseback was a truly armored unit, and it would only suffer once the longbow and crossbow technologies were up to the task of taking down the mount and/or rider at long range. These are expensive people to train and maintain, and once they are available and made, they can begin to dominate the old scrum of hand-to-hand combat by outflanking front lines and attacking with force to shatter most defenses, save those that used polearms as no horse will impale itself on a prepared polearm defense no matter how well trained it is. An AI must have the necessary scripts to properly evaluate such units and decide on their potential as part of an army. This means the game developers and designers must be cognizant of the history and approach of the people of the era a game is in. Yet such AI must also have all the alternatives available to it, so that it can pick and choose among them for what best suits the current condition.
Warfare is the prime area for historical recreation as it involves conflict that changes the course of history, and that course can then be played out over the course of the game. What the player does or does not do will influence the decisions of others in the game, be it AI or other human players. Living individuals can take very different views on what to do given a set of tools and a mindset of what they wish to accomplish. Games that allow for victory conditions based on goals, objectives, or completing a number of tasks can also take place outside of the direct military venue or be a part of wider and extended game play that also includes the military as aspects of that era.
Looking back on Third Reich, it has objectives on the map that, when taken in sufficient quantity, can determine victory conditions, and each Nation or Alliance has its own number to collect. These are strategic objectives, and the point of warfare is to secure them. This can be done through military conquest or via the shift of a government by events under the umbrella of a larger Nation or Alliance. The region of Hungary, Romania and Bulgaria typically do this in a given run of 3R as a pre-scripted event. Random events, drawn at the start of the game, can also put Turkey or Spain into that category. An entire branch of theory and alternate history is one in which Nazi Germany didn't attack the USSR so quickly and, instead, continued the westward push to steamroller Spain and then perform a multi-prong attack on Gibraltar. That single port that allows the UK to trans-ship goods from the Mediterranean to the Atlantic is key to a larger offensive against the UK and, thus, the Allies.
The game rules have stipulations on how to drive fleets out of a port so they can't be there during a ground assault. That is done via paratroop drop, and the German military did have paratroops from very early in the war. Fleets at sea can be kept busy by opposing Fleets, thus a joint strike on Gibraltar using Italian and German Fleets to tie up the British Navy at sea is required. As paratroops are neutralizing the defenses of a fortified position to some extent, a large push from the ground against the prepared forces of the UK in Gibraltar can start, and tactical air assets should be able to assist in that assault to neutralize whatever air assets are used in defense and to generally add strength to a ground assault. It is no easy thing to pull off and requires cooperation between players if there is no single Axis player. The result is a high risk operation with a good chance of success, as the air assets pummel the defenses as the paratroops drop to force the fleets out. After seizing the port the UK's economy is crippled and its BRP allocation per year is greatly reduced. This represents goods from the British holdings in India, Australia, New Zealand and the islands in and around Oceania having to go around Africa and thus be easier targets for a U-boat campaign in the Atlantic. Givraltar is just one of the strategic objectives in 3R and does not come into play often nor easily, and requires planning and a bit of luck.
If performed well, then the Allies are in a bad state to defend the UK and the strategic campaign of U-Boats vs ASW assets shifts in favor of Germany. Even when the US enters the war, the might of the US economy will not offset this shift in strategic advantage even if held for a single year. The moribund African Campaign can now restart for the Germans as there is now a direct supply link through Gibraltar if the Axis forces move smartly across North Africa over French colonies which need to be neutralized if they are Free French. That single operation in the European theater represents something that the German General staff had on the drawing board as a plan as they recognized the threat of an unsecured rear and a two-front war with the USSR as being strategically untenable. Thus doing so is to alter the course of historical events for that run of the game and see what the results are. There are still choices available to the Allies, but they are fewer and harder to execute. Most players won't try this and, instead, try to optimize an eastern assault against the USSR in a mad dash to get strategic objectives and then force any kind of peace, at all. The Axis will still be short a few places, true, but the choices at that point center on the Middle East or the UK itself. An Operation Sealion might be attempted if all has gone swimmingly well after taking Gibraltar and then shifting air assets as fast as possible to the coast across from the UK.
That is the sort of planning and thinking that must go into a plan to change history, and to be done it must be executed well and the player have the game mechanics nearly memorized so that the important sequence of events are prepared and operations can be reinforced. Delay in waiting for supplies can be lethal, as the Winter War demonstrated, yet in good campaign season being out of supply is simply waiting at the last part of the season for the strategic resupply lines to open up, though in preparation for winter that requires no late summer campaign. Spain doesn't have that problems so the 'mad dash' solution across France to Spain and Gibraltar is viable yet requires good execution to pull off.
In the dynastic Grand Strategy RPG that is Crusader Kings II, a much, much wider set of options and limitations are handed to the player given any level of start from simple county to an Empire. Working your way up from the bottom is one of the better and more challenging ways to play as it allows the player to learn the personalities involved and all the factors of culture, religion, dynastic policies for who inherits, and taking part in a Secret Society (or not) with the benefits and drawbacks those bring. Getting a throne and passing it down via one's family is no easy business, as there are many who want power of any sort, thus a player needs to understand the threats in their given area and learn how to deal with them. Bribes can work, so can granting honorary titles, or even landing someone to satisfy them and, possibly, neutralize them into a dead-end position. For those who are part of a dynasty you don't want to offend but do want to neutralize, handing them a City holding which runs under the rules of a republic may be a very viable thing to do.
Thus for a game to feature good mechanics of what happened in any era of history has that as a basis for creating alternative scenarios via game play. The more freewheeling the game is over a historical period or multiple periods, the more the game developers have to create content for the variations in possible types of game play. Short scenarios for a year of two on a single front of a wide-ranging war is relatively easy unless there is a rapid development of technology and deployment of technology via some sort of industrial system. Staging features to be amenable to different rates of research, engineering and production require a system that fits a wide variety of possible products and how to research them, though that may be an out of map system done just by the game engine in a scripted fashion. The more that falls under the player's direct control, the better and more robust the system has to be. A game may be aimed at an historical period as a start date and then move that date back for wider ranging game play, and thus it will have to introduce mechanics to retard the research rate or renormalize the system to make technology seen at the later start date have a higher base cost to it. Either are acceptable as database manipulation techniques. By hard-coding in certain technologies, or locking them behind very steep research costs, a game can then introduce historical changes that they have tried to put beyond the reach of the player. That can be frustrating to a player who spends a large part of their time researching that technology, and then find it granted automagically by the game mechanics running an early start date: good game play would indicate that such technology grants would need to be adjusted if the player has already unlocked them, perhaps kicking off a historical change earlier but having a very low adoption rate for a period of time. In any event, the ability for players to utilize game mechanics to their advantage and optimize them still plays a part in the overall system and vital to alt-history in a given period of history.
Game developers who develop such games need to do a lot of research just to understand the period of history they will be showing and depicting it properly. Stopping early tanks via light infantry is possible and requires a different set of equipment from standard small arms unless that suite of small arms has some effectiveness against early tanks. Ballistics, explosives, toxic gas, and other forms of assault to slow or debilitate a tank might not be well represented in standard combat at anything above the individual level. Representative units can be given a Close Assault Tactics capacity versus armor that changes the base attack score to represent that specialized equipment held by normal units, and anti-tank squads given a major buff to their own CAT, indicated by their representative marker, perhaps. In a campaign that allows the design of specialized units, this form of unit may have a relatively weak attack against softer enemies but have a good attack against armored or hardened enemies. Thus an anti-armor team may be utilizing a Recoilless Rifle group, bazooka armed individuals with their own ammo carriers, or have a squad that is equipped with anti-material rounds for a few individuals with heavier equipment.
The ability to continue such attacks over the course of any given battle may be limited, and that would mean having good training and high accuracy would become a paramount background piece of information for that unit type. Longer training means fewer in the field, and that then requires having a good mix of light units, anti-tank or anti-armor units, and heavier armored units of one's own which could also feature a limited number of tank destroyers (tanks made to take out other tanks). Further back in history the crossbow and English longbow marked the decline of Knights in armor on horseback and specially made arrows or bolts were created for high velocity armor penetration, yet only when these are massed into coherent units and trained as a unit do they become a game changer on the battlefield. The same rule applies, and the training time for a longbow is substantially longer than that of a crossbow, yet arrows fired by such skilled archers may be far more effective than the relatively low training time crossbow groups. Deciding on what to field, what mix of troops to have and how well trained and equipped they are then makes for interesting alt-history game play.
With a wider historical period comes wider divergence from the norm, which requires game developers have a framework for the activities in their game to properly reflect these changes from standard history. The economic system needs to be well defined for the entire scope of the game, and even if it is highly generic like the Basic Resource Point system of 3R, it should have some basis in representing the actual economy and its sub-sectors either by direct investment or simple unit types being built. Any reinvestment game mechanic that alters the game play requires that it have a well understood basis, and that effects are properly measured at the scale of the game, itself. Again with BRPs there is a percentage increase in the base economy of unspent BRP's from the prior year, permanently. There is a partial roll-over effect that can make an economy stronger over time so long as the entire budget is not spent. In a game like CK2 the money is measured in gold pieces, that are, themselves, extremely abstract and not representative of actual gold but a measure of a treasury under control of the player. A system of abstract currency is that there are nebulous ties to the actual, real currencies of a period, which makes an actual estimation of economic strength as measured in historical expenditures impossible. The concept is sound, and investing in trade, military, religious or other buildings will garner something, even if it is just the generally non-fungible personal currencies of Prestige or Piety. Trading in one currency to build a base in another type is a viable and valuable option, and should not be overlooked by any player in games that feature multiple statistics and currencies.
Games are very well suited for tracking things that are mentioned in historical context, but not something that can be easily tracked. Thus, when we speak of the Moral Authority of a religion in historical context, there is no real world way to gauge it: there is no Karma or Piety or Faith currency accrued to the followers of a religion to grant derivative statistics that would drive Moral Authority. Similarly in the currency of Prestige there is no currency that can be tracked, because we can't pin down what, exactly, will drive that in one direction or another. As this is not a publicly traded currency or generated up in any real world way, there is no way to track it. Yet games can establish a framework for these things and track them by attaching that currency generation to offices, titles, holdings, and even to individuals of certain capabilities that are generally accorded to have such things as part of their background, like via a bloodline. And as in the past, so in the future, so that Political Power, the ability to Sway others via National Reputation and so on can apply in the post-medieval setting while the older currencies lose their relative value. If done well then in the base game history will have a very high amount of fidelity to the model, so that players can understand just how the world as we know it was shaped by the forces that drove it forward.
By playing in such a model, however, the players can also move in ahistorical ways that are also allowed by the system as this represents the effect of minor changes in history having a ripple effect, outwards. One can start as a defender of the Roman Catholic Church in Lancaster under threat from the Viking invasion and turn around that threat and then research the history of Christianity and become a Waldensian heretic, spreading that heresy according to the lands held by that leader. I've played as that person, becoming a heretic in the early 9th century and in less than a century it had ripple effects that were felt all the way to the Byzantine Empire. By the late 10th century Roman Catholicism led by the Pope was no longer considered the standard form of Catholicism and the Pope and the Papacy had become heretics as the wildfire spread of that minor heresy hit Europe and even Pagan lands where it was found to be an appealing alternative to standard Roman Catholicism. While actual Waldensianism wasn't invented, the heresy, itself, is a way to examine early Christianity and come up with a variant answer, and the sheer number of heresies that arose demonstrates that the name can represent a set of beliefs rather than the actual heresy created by Waldo. Naming it after the founder that you were playing, doesn't really suit the game of CK2, while the broader definition within that branch of thought does, so that sticks as the defining type. Yet all it takes is the holder in a single county seeking to beat back the threat of the pagans at the doorstep to achieve this, by having high enough learning and going to a religious focus for a decade or so.
The ripple effects are something that historians would shake their head at as 'unpredictable', yet game designers who wish to keep a high fidelity to history create systems for the seen and unseen to help model those very effects. Every time a new game of any historical context is started, then the real world history no longer applies. The game mechanics and systems still DO apply so that things that didn't happen in our history can happen in a game. From that history is shown to be contingent upon minor changes that can have profound effects on the outcomes that shifts individuals, peoples, societies, religions, Nations and the state of the World. This goes beyond the lack of a nail for a horseshoe, yet that very concept demonstrates that history hinges on contingent events and that our current world is made of all those events that happened in a certain way to get the results we honor as history. Playing games with a historical context that go beyond simple military ones requires some knowledge of the game mechanics and what they represent. With that understanding and knowing how events are modeled in the game, different results by treating events in a different manner can and do yield different results. That is the fun of playing such games as games: they allow for a greater leeway in asking the 'what if?' questions of history and seeing what the results might have been. Alternate History used to be left in the hands of those writing stories, mostly science fiction or fantasy, and that was joined by historical context games by the mid-20th century and is now a permanent part of the gaming landscape.
History professors and professionals may not like what has been done by these games, but that doesn't really matter as they haven't knuckled down to actually make good historical frameworks that can be derived from what we know of historical facts and events. The field was left wide open to game designers who knew and loved history, though not as professionals: their heart, like that of a Waldensian Count, went in a different direction. And as James Burke points out, the pinball effect of history is something that is very real and in play not just in the past but in the present as well. The interconnected world of today isn't just about global systems of industry, commerce, tourism, culture and the like, but can be boiled down to asking a question: if you are in an elevator and the power goes out for good, what do you do? How the real world changes due to the history and the systems behind it is a very real thing to understand. Any gamer that delves into historical games will realize this as that is what attracted them to that game from the start. What you do with history is all fun and games. What history does to you, that is another matter, entirely.
