Irken Empire

The Irken Empire is an aggressive expansionist force headed by the war-like Irken race. The Irkens are bent on galactic conquest and, with the aid of their massive armada, they may actually achieve this goal. The co-ruling emperors of the Irken Empire are the Almighty Tallest, Red and Purple.

Enemies
The Irkens are a bloodthirsty race, as Irkens have a superiority complex and feel a need to conquer other worlds. Because of this, the Empire has many enemies.

The Itaoc Empire
Before Irk rose as a Galactic Power, The Itaoc race was a force to be reckoned with, in fact their warlike and barbaric nature surpasses their own bloodthirstiness in many ways. By the 13th Century durring Earth's history, they were defeated by the Irkens, due to their superior technology. The escaped Itaocs fled to unknown regions to rebuild their civilization, while also hoping to get revenge on the Irkens for conquering their once proud planet.

The Resisty
The Resisty is an organization created to overthrow the Irken Empire, and the Resisty's members are presumably members of planets conquered by the Irken Empire. The Resisty attempted to pierce a hole in the Massive's sidepods, which is full of snacks, and the ship's one weakness. However, they failed in this task, and merely succeeded in lasering "RESISTY ROCKS!!!" on the sidepods (which was then washed off). They are later seen on the Irken snacking planet of Foodcourtia in The Frycook What Came from All That Space

Meekrob
A common enemy of the Irken Empire is the Meekrob, a species made of pure energy. The Irken Empire and the Meekrob are currently in a war.

Smikka Smikka Smoodoo
Smikka Smikka Smoodoo of the Screwhead race attempts to start a rebellion against the Irken Empire, but the furthest he ever gets to starting one is switching the names on two packages. That may sound like nothing, but this actually, if Invader Zim had continued, would have had severe consequences: the malfunctioning SIR units originally intended for Zim would have been sent to Invader Tenn on planet Meekrob. Once their package was opened, the psychotic robots wreaked havoc, causing Tenn to be exposed, and ultimately sparking a huge battle between the Meekrob and Irkens. This would have later build up to the unmade Season 2 finale, Invader Dib

Dib
The only human enemy the Irken Empire has, since the Irkens are aware of the human race's lack of powerful technology, it's obvious they wouldn´t consider Dib an actual threat. However, he has, on occasion, proved himself to be a formidable force, as the unfinished series finale "Invader Dib" would have shown that Dib would've infiltrated Irk.

Vort
The Irken Empire was originally in alliance with the Vortian race, who supplied the Irk with excellent technology. The Vortians designed The Massive, the flagship of the Irken Armada. However, Zim created an infinite energy-absorbing monster at Vort Research Station 9, which subsequently devoured Almighty Tallest Miyuki, and later Almighty Tallest Spork when it returned to get its collar back. This presumably ended the alliance between the Irken Empire and the Vortian race. Vort, recently conquered by Invader Larb, is now Irk's top military research prison.

Blob Species
The Irken Empire is presumably in alliance with Eric the Blob's species, as Eric installed a bio-scanner on the planet Vort when it had been conquered to make sure that no Vortians escaped. However, some did (presumably Captain Lard Nar of the Resisty) in trash cans.

Planet Jackers
The Planet Jackers are one of the few races that the Irkens have not tried to directly conquer, nor were they forced into an unequal alliance with them like the Vortians (who were eventually conquered outright). They are practically the only race that has been shown to deal with the Irkens on more or less equal terms, signing the Irken - Planet Jacker Treaty with them which prohibits the Planet Jackers from destroying planets marked for conquest by the Irkens.

Hobo 13
The Irken Empire is presumably in alliance with the desert planet used for military training--Hobo 13.

Conquered Planets

 * Blorch
 * Callnowia
 * Conventia
 * Conveyor Belt Planet
 * Devastis
 * Foodcourtia
 * Judgementia
 * Storage Planet
 * Vort
 * Dirt