Be it Apokolips, Citadel, or Dominion, DC Comics has seen many large intergalactic empires come and go throughout the decades. While most pale in comparison to the size, scale, and scope of Marvel's Kree, Skrulls, and Shi'ar empires, many of DC's are able to extend their reign of power thanks to the enormity of their planets, populations, and longevity.
The biggest empires in DC Comics often use their cosmic might to threaten Earth, requiring the most iconic superheroes to thwart their quest for interplanetary dominance. While some have been more successful than others, the largest DC empires remain a looming threat to universal peace and harmony.
10 Apokolips
Introduced by Jack Kirby in 1971, Apokolips is a massive imperial ecumenopolis ruled by the ultra-powerful supervillain Darkseid. The hellish underworld is big that it dwarfs multiple galaxies and is able to launch attacks on multiple cosmic dimensions.
Set in the Fourth World where the physical makeup of all matter is much larger than on Earth, Supergirl once traveled to Darkseid's homeland of Apokolips without using a scale-correcting Boom Tube and was reduced to the size of an insect. Protected by Steppenwolf, Kalibak, Paradaemons, Female Furies, and more, Darkseid's Elite Forces have retained Apokolips' enormous might to consume planets and cause Armageddon-like destruction.
9 The Citadel Empire
Introduced in 1981, Citadel was a fascist evil empire that extended its reign over several planets. According to DC Fandom, Citadel conquered 21 of 22 of the discovered worlds in the Vega star system, indicating its vast colonial reach.
Ruled by Blackfire and Harry Hokum, the Citadel's forces include the native Citadelians, the Branx Warriors, the Gordanians, and the wicked Spider Guild, all of which bolster the empire's population and military might as a means of staying in power. While not quite as large as its Marvel counterpart, the Citadel aligned with the Shi'ar Empire in the DC universe set in the "Crossover Earth" event, which increased the size and strength of its imperial hold.
8 Daemon Empire
Made up of the reptilian alien race known as the Daemonites, the Daemon Empire spent millennia warring with their more benevolent counterparts, the Kherubim, as they fought for dominion over the planet Khera in the Milky Way.
While it's hard to pinpoint the exact size and population of the Deamon Empire, the hostile species conquered vast alien worlds and expanded its reign of power by breeding with the alien species that they colonized and evolved into new forms throughout history. According to Alien Fandom, the Dameon Empire spans multiple galaxies, which indicates their cosmic influential reach in DC Comics.
7 Dominion (The Dominators)
The Dominators are an alien race of intergalactic conquerors from the outer cosmos who rule the imperial planet of Dominion. The massive Alien Alliance presides over one of the oldest evil empires in DC lore, extending its influential reign across the 20th and 31st centuries.
Represented by Gunther, Sakritt, Xylon, and Ambassador Wuuthlan, the Dominators once conquered Earth after the moon was destroyed, which expanded its empire until the Post-Infinite Crisis took place. Composed of several city-states throughout Dominion, the Dominators used their political pacts with the United Planets (akin to the United Nations) to sign treaties and keep their homeland protected, enabling the empire to keep its stranglehold on their opponents.
6 D'rahn Empire
One of the oldest alien species in the Wildstorm Universe, the D'rahn Empire managed to conquer Earth a millennium before the Kherubim and Daemonites fought for the imperial right to rule. The carnivorous humanoids are ruled by Lord Typhon and have primarily been able to conquer enemies with their female enlightenment abilities.
Aside from being able to fly, survive in outer space, and use their superhuman strength, speed, and durability to outlast enemies, the female D'rahn are able to evolve or devolve any creature they touch with their inherent enlightenment abilities. Combined, these forces have led to the D'rahn Empire's social hive behavior, giving them massive strength in numbers.
5 Kherubim
As staunch opponents to the Deamon Empire, the Kherubim was able to build its massive empire by utilizing expansive Planet-Shaper Engines to conquer the Titanathropes on their home planet of Khera before batting the Daemon for a millennium. After turning the Daemons into their slaves, their empire grew considerably.
The near-immortal Kherubim also expanded their empire thanks to their political order, organized caste system, advanced technology, and its legion of Kherian "Superman Class" warrior conquerors who excelled in physical combat. Bolstered by the rank-and-file Lords, Adrastea, Warlords, Shapers, Coda, Skien, and Bladesman, the Kherubim Empire is easily one of Wildstorm's biggest DC empires.
4 The Khunds
Marked by an eternally dark home planet of Khundia, the Khundian Empire formed over 3,000 years ago when their ruler Kobald managed to defeat the easily distracted DC villain Doomsday. Despite their penchant for aggression and fighting to the death, the Khunds' lifespan and increased capacity to reproduce allowed them to advance their bloodline and continue their imperial conquest.
Part of the Khundian Empire's conquest included allying with the Dominators to attack Earth, successfully destroying Australia in the process. After the attack, the Khunds remained in power for 1,000 years until the 31st century and largely kept to themselves. However, it's their ability to reproduce past the age of 75 and enjoy an average lifespan of 95 years that kept their dominion intact for so long.
3 New Genesis
Introduced by Jack Kirby in 1971, New Genesis was reborn on Earth-0 as "a highly powerful empire" (via DC Fandom) ruled by Highfather, the most powerful New God. The home planet of the New Gods was formed when Galactica and its evil twin Apokolips split their home world of Urgrund in half.
Home of the Genesisians, Primitives, Bugs of New Genesis, Forever People, and the omnipotent Infinity Man, the deified holy land also features the floating metropolis Supertown, aka Celestial City. Along with these forces, Highfather has been able to sustain an eternal war with Apokolips and keep the empire intact by channeling the mysterious power of the Life Equation to combat Darkseid.
2 Sangtee Empire
Introduced in 1992, The Sangtee Empire was a brutally misogynistic kingdom ruled by Emperor Kreel, a woman disguised as a man. Proving to be one of Wonder Woman's toughest adversaries, the Sangtee Empire outlawed the presence of female human beings while the nobility kept Kreel's true identity a secret.
According to DCFandom, the Sangtee Empire was "a collective of planets," suggesting its massive galactic stature in the New Earth universe. With women enslaved on the planet, the Empire manages to imprison Wonder Woman, Natasha Teranova, Julia of Daxam, and H'Elgn. Fortunately, the foursome rebelled and successfully abolished female enslavement, which weakened the empire considerably.
1 Warworld
Introduced in 1980, Warworld was an imperial planetoid that had the ability to travel through the cosmos on a whim and extend its cosmic reign easier than most. Ruled by the tyrannical Mongul, the Warworld empire spanned from Pluto to the Sol Star System, underscoring its astronomical cosmic expanse.
According to DC Fandom, Warworld is physically "bigger and sturdier than a dwarf star and equipped with weapons able to obliterate planets easily." Protected by the warmongering Warzoons, the satellite empire become so powerful that Superman and Supergirl had to step in to stop Mongul, but his weapons easily overpowered both Kryptonians at first. Once the duo managed to defeat Mongul, they admitted that only Warworld was big and powerful enough to destroy Warworld, suggesting its extreme cosmic influence.