I recently completed the mobile game Final Fantasy Dimensions, which brought back the series’ tradition of using an evil empire as the villain. This motif is one that is present throughout most of the Final Fantasy series, and it is easy to see why. Unlike the Dragon Quest series — which usually focuses on an intangible, mystical or demonic villain as the bad guy (like Rhapthorne from DQVIII or Demon Lord Nimzo from DQV) — an evil empire strikes an instantly recognizable chord with the gamer. It represents tyranny, oppression, subjugation, and the loss of the individual against a mass uniform force. The very word empire evokes so many sharp images in our minds due to our own background and history.
From a gameplay standpoint, the empire makes sense as an antagonistic force since it not only provides an overt villain, but also offers a large, overarching and layered game mechanic that can provide many colorful villains or characters under one umbrella (e.g. in Dimensions there are eight generals of the Empire's armies, and oh boy do you get to fight all eight of them eventually). At the same time, it also provides a counterpoint for your party: You are the individuals fighting against the masses that wish to conform you and crush you to a pulp. This provides not only high stakes for your plight but also consistently pushes the game toward an eventual showdown between your "individuals" and the empire.
Final Fantasy II was the first game to really use the evil empire motif in the series, as the main bad guy was the Emperor himself. It is interesting to note that this Empire, while an ever-present force in the game, is very nebulous in its purpose and its constituency. Its armies seem to be half demonic rather than just human, and the seem interested in subjugating every land just for the sake of subjugating them. They aren't concerned with human rights or diplomacy, just domination by the right of conquest. Even the Emperor himself is kind of a mystery. He appears kind of androgynous, he is definitely not human, and he has incredible magical powers and the ability to transcend death itself, all without any real explanation. He just seems to enact evil because he is evil incarnate.
The next time an evil empire shows up is in Final Fantasy IV. The idea is thrown on its head right at the beginning as the protagonist, Cecil, starts as their “Dark Knight.” The game opens with him invading Mysidia and forcefully taking their Crystals for his own country, Baron. It is only when he unknowingly destroys yet another village through subterfuge that he sees his country for what it truly is. Once he finally confronts his King, he realizes that Baron is only a front for a much larger empire under the evil Golbez, complete with its own set of Generals (the Four Fiends), and several bases of operation (the moon, the Tower/Giant of Babil, etc). Though the idea of the "evil empire" is less overt in Final Fantasy IV (as your quest seems to be focused against just Zeromus/Golbez), keep in mind that each of your characters joins the quest due to a particular loss at the hands of the "empire" (the ninja Edge, the prince of Eblan, had his parents transformed into monsters at the hands of one of the Four Fiends), and the whole game focuses on righting these wrongs and stopping Golbez from invading the various kingdoms.
Exdeath in Final Fantasy V acts like an evil emperor himself. He has his own castle in another dimension from which he wages war upon the world, and a strict set of henchman and generals with which to enact all his plots. He invades, disrupts, and is bent on world domination/destruction. Again, like Zeromus and the Emperor, he only seems to be concerned with being evil for the sake of evil's sake. As the Emperor seems to be more demonic than human, and Zeromus is a living embodiment of wrath, Exdeath is the result of evil being sealed into a tree and manifesting into human form. All the "emperors" of the evil empires thus far are not even human foes but otherwordly beings that, aside from being uber-villains and despicably evil, are impossible to relate to on any human level.
Final Fantasy VI was the first game to have an empire based truly around and through humans. The emperor in this case is Gesthal, a human man with very human motivations: greed and a hunger for power. He is no warlock or grand sorcerer, but instead must use his troops, diplomacy, and subversion to get what he wants. His followers are also very human. General Leo is a man who lives by a strict code of honor and refuses to resort to some of the empire's more draconian tactics. Kefka is a general who was driven insane by the process of artificially infusing magic, which provides him with a great motivation for his evil rather than just mindless destruction. The troopers of the empire are all human as well, fighting and dying for their country with patriotic gusto. Even after the shift to the World of Ruin halfway through the game with the empire being utterly destroyed, we have a haunting reminder of it with Kefka's Tower, constructed from the ruins of Vector, the empire's capitol, and standing as a monument to madness in the middle of the ruined wasteland. Simply put, Kefka and the destruction he has wrought is because of what the Empire first enabled.
Final Fantasy VII takes the idea of an "empire" and modernizes it by turning it into a major corporation that basically owns all industrialized products and services on the planet. Unlike most of the other games where the empire is trying to dominate the world, the Shinra Corp. in FFVII has already won. It owns most of the cities/towns in the world, is supplying them with electricity and energy, and it controls via marketing and propaganda what the public sees of their more "imperial" activities. It even has its own "emperor" with its CEO President Shinra and then later his son Rufus, and a strict hierarchy of bureaucratic positions under that, including the Head of Public Safety, Heidegger, the Head of Weapons Development, Scarlet, and the Head of Science Research, Hojo. The role of the "individuals" who stand against the empire are a radical eco-terrorist group who are trying to destroy Shinra's ability to harvest Mako out of the planet. FFVII definitely provides an interesting spin on this motif.
The evil empires in both FFVIII and FFIX are actually puppets for the main bad guys in their respective games. Galbadia is a military dictatorship in FFVIII that is under the control of its President, Vinzer Deling, and is constantly seeking to expand its border through aggressive military actions, tough diplomacy, and subversive warfare. However, about halfway through the game, its president is killed by the Sorceress Edea, who turns out to be controlled by the actual main villain, Ultamecia. Once this is revealed, the empire crumbles and most of its military deserts the country.
Final Fantasy IX pulls a similar scheme with Kuja manipulating Alexandria and its ruler, Queen Brahne, to collect the Eidolins for him under the pretense of gathering more military strength and helping her conquer more countries. Once her usefulness has reached its limit, Kuja strikes down the Queen and Alexandria turns from an evil empire into a benevolent realm as your party member Garnet becomes its Queen. It is one of the few instances where the empire actually redeems itself over the course of the game.
In FFX the "evil empire" is more the chief religious sect, the Church of Yevon in Bevelle. In this game, though, your party never directly confronts the "empire" except for one member, Seymour, who is a corrupt Maester driven insane and power hungry. Seymour seems to attack your party independently, but Bevelle, aside from a few instances, never seems to attack your party directly or interfere with their quest.
For Final Fantasy XII, a game that revolves around a plot of political intrigue, it seems fitting that the main bad guy isn't the Empire of Archadia itself, but merely a group within that is led by Prince Vayne Solidor who hopes to steer the Empire into a war that would threaten the sovereignty of its neighboring kingdom of Rabanastre. Other members of the kingdom are more than happy to avoid war, including Vayne's own brother Prince Larsa, and it is certainly an example of an empire with human motivations and desires. Vayne himself isn't a wholly evil character, but one that acts on his own beliefs and convictions, believing that he is doing what is truly right for his country and humanity as a whole.
Final Fantasy XIII is almost a modern day iteration of the empires from FFII, IV, and V: one that is driven by an unrelatable monster that only wants to destroy everything for reasons that are incomprehensible to a human mind. Barthandelus, the main antagonist in FFXIII, poses as the Primarch of the Empire on Coccoon but is really one of the god-like Fal'Cie. His motivations, among one of the many confusing things in this game, is to drive the party to destroy the world (of which he is the ruler), so that the maker of all things will finally return to the world (?!?). The idea seems to take a few steps back in this game, as the “evil empire” went from being a living, breathing entity back to a uniform mass of soldiers without any true humanity (you really do kill droves of those guys in the game and never feel any sort of remorse), and a main villain that is just mind-boggling.
The idea of an “evil empire” is an interesting motif that continually pops in and out of the Final Fantasy series, and it has been fascinating to see how it has transformed over the years and even spilled out into other games. Chrono Trigger doesn't have an evil empire, but it hints at the end of the game that one will arise in the future due to the actions of your party by allowing the villain Dalton to live. Skies of Arcadia has the most tried and true version of the evil empire, by providing a series of ranked generals or admirals for your party to fight throughout the game. Even Western role-playing games like Fallout: New Vegas have several evil empires depending on your personal perception and if your character is good, neutral, or evil. The NCR is seemingly a benevolent force, but it is bloated, inefficient, and riddled with bureaucratic red tape, while Mr. House rules over New Vegas with an iron fist, but provides power, food, shelter, and water to an otherwise inhospitable wasteland. Even Caesar's Legion with its utterly barbarous tactics and cruel enslavement of other cultures brings a certain order to the chaos of the wasteland.
This motif is one that seemingly pops up all the time in the realm of video games. It is a wonderful conceit that helps provide high stakes, fun gameplay options, and some colorful opponents. Whether you are wresting control of Mt. Olympus from Zeus and the Greek Gods in God of War III, or fighting against the Private Military Complex run by Liquid Ocelot in Metal Gear Solid 4, there will always be a larger than life opponent for your protagonist to fight against. Let's just not forget which series really pushed this idea to the forefront, and has been doing so for decades!