Updated: Mar 5, 2020
Video games are often built in a fantasy world, where game designers can design however they want as long as players feel intrinsically comfortable - however, some games are having story or mechanics based on real historical periods or events, with some imaginary elements into it. It is always a hard question for historical game designers to think about: how to balance the reality and imagination, so my players can not only feel they are immersed into this historical world, but also enjoy playing it?
Going completely realistic is often not a good design - certainly, many hardcore gamers like that, but most customers are not hardcore. However, for historical games, I think there are some aspects that the games must be as realistic as possible:
The greater location is the first and the most important one. For games using a smaller map like a city, it might not be so obvious since no one knows the exact city appearance during historical time, but the developer should at least make the locations of landmarks relatively accurate. This is extremely important in historical simulation games that use an entire country or the entire earth.
For example, Hearts of Iron IV allows players to act as the leader of a country or faction in the world during WWII. From the accurate location, players not only learn geographical locations of all countries at that time but also can analyze why did some countries matter during WWII because of its location. Think about if the United States bounded on Germany in the game - how ridiculous people would think! The location of a country is extremely important during any war, that is why people are studying Geostrategy. Players who like history will not be happy about that because they cannot simulate the exact situation that the country faced at that time.
A startup map of Heart of Iron IV 1936 scenario.
Also, if the developer made some mistake in a certain country's location, people from that country won't feel good because they might think the developer didn't care about their country at all. I can understand developers make mistakes in very detailed locations since being historians are not their jobs, but I will be excited if they make the small things accurate.
The population can also reflect the degree of reality. The population is one of the most important factors for any historical moment - before the Industrial Revolution, the number of people represented the degree of productivity, and further determined how many soldiers could this country provide in total (of course, even now the population is one of the most important resources of a country). Most historical games emphasized the importance of people, that is why many games are essentially competitions of population, like Victoria II by Paradox Interactive, each unit of population represents a group of people that perform a certain functionalities in the country at that time, and form the basis of the economy and politic of this game.
Not only the classification, but also the number should not be too irrational - for example, in the Japanese Sengoku period, the biggest battle had the number of soldiers around 70,000 vs 80,000. However, in Nobunaga's Ambition: Kakushin by Koei Tecmo (use KT below), the end game is always like millions of soldiers stay in just one castle - can you imagine a WWII happened in a small castle (and each castle typically have less than 5,000 soldiers when the game starts)? I think a game can have some degree of exaggeration on population, to give players positive feedback on their mastery, but not too much. KT also found out this was a problem, so in the later Nobunaga's Ambition games, the population of Japan hasn't gone this crazy anymore.
Notable characteristics of historical moments. Though many games had imaginary stories based on a real event (like many entires of Assassin's Creed), to provide players a better immersive experience, especially for players who enjoy experiencing the historical moment, developers should research much on how to re-establish this event. Are all important related characters included? How should citizens behave before, during, and after that historical event? How to integrate the imaginary story happened on the protagonist into the real historical event seamlessly or without violating the truth? etc. Players may not notice how well the game did if the game did a great job, but they will notice how bad the game did if the game failed some key aspects. A small moment I liked in Assassin's Creed: Origins was petting the cats - since Ancient Egyptian worshiped cats, there were many cats all over the game, and players should not ever hurt them at all, otherwise the player would experience sync failure immediately and must restart from the checkpoint.
Yes, you can pet cats in Assassin's Creed: Origins.
I really want to talk about the Civilization franchise. They are great games, I played Civilization V a lot and also some VI, but I don't classify them into the genre of the historical game, though the entire franchise is considered as historical games. It is simply a nation simulator that every time player starts from the same era with almost the same technologies across the game, no matter if the country has appeared at that time (like the United States in B.C.E. 2000). The leader of your civilization is someone iconic from the history of this country but never dies. The special traits of each civilization are mostly just stereotypes of that country and only serve for gameplays. This franchise is more like a turn-based 4X human development game with tons of historical words.
I think the following aspects are the hard parts of designing a historical game:
Cultural variation. This is an iconic problem for developers who are not from the country in their game. A very great example is Creative Assembly (use CA below), who is known as the developer of Total War games. They released Total War: the Three Kingdom last year and received very positive feedback. The game is great, CA spent a lot of time on researching the architecture, weapons, clothes, etc., and these things are restored pretty well in the game. However, if you are a Chinese, you will laugh when you found some situations like Liu Bei, who advertised him as the force to restore the Han Dynasty, invited you to fight against the Han Dynasty, or Guan Yu, who is worshiped by Chinese people because of his loyalty, betrayed Liu Bei and saying his life is more precious than being loyal after he got defeated. I do believe CA's efforts on this game, but obviously, they didn't care about any internal bonds among the famous people in that era, all characters in the game are only different by image and attributes.
A counterpart can be the Romance of the Three Kingdoms (game) by KT - it is not necessarily a better game than TWTK, but KT did try to restore the true personalities of each famous people in the game (though KT is not a Chinese company, Japanese culture is much closer). However, all historical games made by KT are full of great man theory, which empathized with the impact of certain great people that are commonly processed artistically, which are even more imaginary on the other hand. The culture barrier is a very important aspect that blocks the developer to make a realistic feeling game, and I highly recommend the developer should hire some experts or at least a group of people from that country when making historical games, to alleviate problems caused by the cultural variation.
Liu Bei, Guan Yu, and Zhang Fei are blood brothers. In Romance of the Three Kingdoms 14, If they are close together in a battle, the skill will be super effective and a special visual effect like above will show.
Real history vs. Common View. Most people have only studied history for fulfilling the school requirement; they mostly know from novels, TV shows, or friends, etc. How should the game developer deal with it if the common view of a character or a country is dramatically different from history? The small portion of people who liked the related history might like making it realistic, but most people might instead say the game is not real because it is different from what they heard.
For example, Most Chinese people know the history of Three Kingdoms from Romance of the Three Kingdoms (novel), which has many events hugely different from history. I played KT's historical games for a long time, and I found that KT used solely imaginary versions of historical events in their earlier games, but gradually accepted some realistic versions in the later games - sometimes the profiles of the characters will tell you the difference between the novel and the history. In their Dynasty Warriors series, they have created their own Three Kingdom universe that each character has a well-designed, realistic-imaginary mixed personality, and they are sold very well.
In its game Nobunaga's Ambition: Tendou, it was so funny that KT introduced some hypothetical statements that were totally ridiculous and fake but well-known by many people, like making Uesugi Kenshin a woman because he has not married and had a child in his entire life. Players actually liked it so much even though they knew it was just a parody.
Red lines: "What if Uesugi Kenshin was a girl, just like the rumor..." (The bottom left person is the original version)
Ability to change history. Historical games often target players who like certain periods in history, but it doesn't necessarily mean players must follow the history. As far as I know, almost all non-linear historical game is charming because players can rewrite the history in the game. What if I play a faction that was defeated in history to unify the country? What if I play the weakest country in this game to conquer the entire Earth? These all sound excited since people cannot do these things in real life.
This happens on many people who read Romance of the Three Kingdoms (novel), since the novel was from the perspective of Shu Han, so readers are more empathetic about Shu Han than other factions in the book, and often thought about what if Shu Han became the winner in the history -a big number of players would choose to play Liu Bei in Romance of the Three Kingdoms (game) and unify the country because of this. Even TWTK gave a great moment to Liu Bei in the trailer because he is one of the people who can attract most players who know the Three Kingdom history.
On the other hand, changing the history is sometimes criticized because of many ethical reasons - like players play Axis powers to conquer the world, which is politically incorrect and sometimes crossed the red lines of many people. I would also like to play those defeated countries because it could be super fun and I don't think game should be limited this much, but I do believe historical games should never be built based on ignorance - developers who make such games should always keep neutral and not introduce biased political opinions and unacceptable actions like genocide into the game, and should always do research as much as possible to make players not feel offended before designing an imaginary outcome.