The Justice League was formed after the invasion of the imperium (White Martians) by the seven heroes who responded to the catastrophe. The team was converted after the thanagarian invasion into the Justice League Unlimited. The League's first headquarters was in the Watchtower I, and after its destruction has given the same name to all of the leagues following bases.
The Imperium invasion and formation Edit
Following Darkseid's invasion of Earth, Superman regained the majority of the world's trust after being brainwashed and used as a pawn. Though doubts remained regarding the Man of Steel's reliability, none put more faith in the hero than Senator J. Allen Carter. Carter proposed world peace through weapons disarmament, and nominated Superman for the job. Though skeptics aired their grievances, the World Assembly passed the motion and Superman set to work. As Superman finished disarming the weapons of destruction, meteors rained down upon Earth. From the wreckage, massive alien creatures appeared, and without hesitation made their intentions clear: conquest. Superman and Batman rushed to the scene, throwing everything within their arsenals at the creatures but their efforts seemed in vain. As the world panicked about the newest alien invasion, Superman fled the scene. Batman tracked the hero to a US Government base. Investigating further, the two discovered a different alien held prisoner there. Freeing him, the man introduced himself as J'onn J'onzz, but the newly-formed trio quickly found themselves under attack by the Imperium. The trio was still outnumbered, but not for long. At a critical moment, the Green Lantern John Stewart, Hawkgirl, Wonder Woman, and the Flash arrived on the scene. The Imperium forces fought back, but they lost; Earth's heroes had assembled. J'onn explained the Imperium Invasion. The septet then broke into three groups, each set on destroying the Imperium factories created on Earth. The heroes fought valiantly, but to no avail. The Flash and Green Lantern made a hasty retreat, while Superman and Hawkgirl were captured. J'onn, Batman, and Diana discovered a method to defeat the Imperium, but in the end only Diana and J'onn escaped. The four remaining heroes regrouped at Metropolis, and prepared to free Hawkgirl and Superman. Keeping a relatively low profile, the heroes managed to subdue the few Imperium forces to cross their path, but eventually were captured as well. Reunited with their friends (albeit via captivity), the heroes were shocked to discover the Imperium organizer to be none other than Senator Carter. The real J. Allen Carter had perished on Mars during a space expedition. Using his persona to their advantage, the Imperium tricked the world into disarming itself. The Earth disarmed, no obstacles remained to prevent their invasion. Earth's heroes, however, proved too resilient. Batman freed the other six, and the group destroyed factories and armada. In the aftermath of the invasion, Batman built and the activated Watchtower, set to orbit around the Earth to act as an early warning system. The heroes recognized the Earth's need for protection, and the Justice League formed.
The Justice League Edit
Though the team had formed, threats continued to face both the world and the galaxy. At each turn, the team faced greater and greater challenges; however, their combined strength continued to prevail. Combining their strength, however, was no easy task. The team rarely worked as a collective group. Often times members would place personal goals over those of the League and the Earth. Each member had his or her own method for dealing with criminal activity: Superman and Wonder Woman, for example, embodied a "shoot first, ask questions later" approach, while Batman and John Stewart preferred concrete evidence and planning to blindly throwing punches; Hawkgirl and J'onn J'onzz often had difficulty empathizing with humanity. At times, their differences caused the team great turmoil, and the group nearly split on several occasions (Gorilla Grodd having the most success with his Secret Society). Despite their differences in approach and definition of heroism, they slowly learned to trust one another. For example, though Batman and Superman never completely saw eye to eye, in a small tribute to the (presumed) deceased Man of Steel, Batman admitted he had nothing but respect for the hero's approach and ideals. The two often bickered, but the interaction between John Stewart and Hawkgirl fostered a romantic relationship. Diana grew more accepting of "man's world" and had something of a romantic fling with Batman. The League, however, would not face its greatest challenge until the invasion of the Thanagarian military; not only was another alien force threatening Earth, but the League was also betrayed by one of their own.
The Thanagarian invasion Edit
The Thanagarians came to Earth claiming to be there to defend it from the Gordanians, who had seemingly just attacked Washington D.C. It was revealed at this time that Hawkgirl, who had previously claimed to be on Earth by accident, was sent here by the Thanagarian government as an advanced scout. She also revealed to GL that she was engaged to Hro Talak, the leader of the Thanagarian forces on Earth. Batman soon discovered that Hro Talak and the Thanagarian army staged the Gordanian attack. Shayera was torn between her loyalties to the League, and to her people. Not knowing what her people were truly up to, she betrayed the League and used her knowledge of their weaknesses to help her people imprison them. After the League escaped, Shayera learned that the Thanagaians' plan would lead the Earth's destruction. She again switched sides and aided her former teammates in stopping Hro from completing his mission. At the cost of the Watchtower, Batman destroyed the Thanagarian machinery. Filled with self-doubt and knowing many people would never trust her again, Shayera resigned from the Justice League.