In each Gundam Fight, the nation which won the previous tournament is permitted to devise its own special rules for the League Finals. In the case of the 13th Gundam Fight, Prime Minister Wong Yunfat of Neo Hong Kong has decided to pit the top contenders from the League Finals, plus the defending champion, against each other in a final elimination round called the Battle Royale. The last fighter standing will win the tournament and earn the title "Gundam of Gundams."

In the Future Century world, the name "Gundam" denotes the mobile fighters created specifically for use in the Gundam Fight tournament. Their name is derived from the lightweight and ultra-tough Gundarium alloy used in their construction. Many attributes of these Gundams—the Mobile Trace System that controls them, the Gundarium alloy from which they're constructed, their size and armament—are determined by the regulations of the Gundam Fight International Committee. Nonetheless, each colony nation has considerable freedom to showcase its own newest technologies.

The Gundam Fight is a martial tournament held every four years to determine the leadership of the United Colonies Federation. The winning nation earns control over Earth and all its orbiting space colonies. This system was established by the Gundam Fight International Treaty, and its conduct is governed by the seven articles of the Gundam Fight International Regulations.

The Gundam Fight is traditionally divided into four phases. First, during the month prior to the start of the tournament, each colony nation sends its representative Gundam to Earth. Then the tournament is declared open, and the Gundam Fight begins; at this point, any Gundam which has not yet arrived on Earth is disqualified. The third phase is the Survival Eleven, an 11-month period in which the Gundam Fighters wander the planet, seeking out rival fighters and battling them in spontaneous duels.

At the end of the Survival Eleven, the Gundams which have made it through this elimination process gather for the fourth and final phase of the Gundam Fight, the League Finals. These finals are hosted by the nation which won the previous contest, which now has the opportunity to introduce special rules of its own choosing. Whatever the process used in these finals, the winning contestant is awarded the title "Gundam of Gundams," and his or her home nation assumes leadership of the United Colonies Federation.

Here are the nations, with their representative Gundams and pilots, which won each of the twelve previous Gundam Fights.

The delicate balance of power between the colony nations was upset by the three consecutive victories of Neo England's Gentle Chapman. Following Chapman's third win, the 12th Gundam Fight was postponed for four years due to the unstable political situation, and so it wasn't until F.C.56 that Neo Hong Kong's Master Asia at last brought an end to Neo Britain's 16-year domination of the United Colonies Federation.

At the dawn of the Future Century, Earth's ruling classes fled the overcrowded and polluted planet to live in orbital space colonies. By the year F.C.2 the planet had lapsed into anarchy and global warfare, which escalated into the devastating Earth Chaos War. The space colonies responded with the formation of the United Colonies Federation, which intervened to end the war and placed Earth's nations firmly under the control of their corresponding space colonies. However, the colonies then began a struggle for leadership of the United Colonies Federation, which threatened to escalate into a second Chaos War.

By F.C.6, the rival colony nations were engaged in a technological cold war. To avert a new conflict, a United Colonies Federation military advisor named Professor E.C. Ducer proposed the creation of the Gundam Fight as a more peaceful means of resolving the leadership struggle. According to Ducer's plan, the colony nations would hold a martial tournament every four years, with each nation represented by one Gundam mobile fighter and its assigned pilot. These Gundams would then battle each other in a year-long elimination process, with the ultimate victor earning his nation temporary leadership of the United Colonies Federation.

The colony nations decided to accept Ducer's proposal, and soon reached agreement on the Gundam Fight International Treaty. This treaty established a Gundam Fight International Committee, which drew up the list of rules and regulations which have governed the Gundam Fight for the last half-century.

The following are the seven articles of the Gundam Fight International Regulations.

The greatest single factor that determines the prowess of each Gundam is its human operator. Known as Gundam Fighters, these elite combatants serve as their nations' chosen representatives. The standards for a Gundam Fighter are exceptionally high, as success in the Gundam Fight demands not only phenomenal fighting skills, but also superb endurance, reflexes, and physical conditioning. In particular, the tournament's emphasis on close combat has led to a resurgence of interest in the martial arts, especially after the surprise victory of Neo Hong Kong's Master Asia in the 12th Gundam Fight.

The League Finals are the fourth and final phase of the Gundam Fight. These finals are hosted by the nation which won the previous contest, which may introduce special rules of its own choosing. Whatever the process used in these finals, the winning contestant is awarded the title "Gundam of Gundams," and his or her home nation assumes leadership of the United Colonies Federation.

In the 13th Gundam Fight, the League Finals are hosted by Neo Hong Kong. As the finals begin, Prime Minister Wong Yunfat introduces his own special rules, according to which a series of one-on-one battles will be used to select the participants for a final Battle Royale elimination round.

The Survival Eleven is the third phase of the Gundam Fight. During this 11-month period the Gundam Fighters wander the planet, seeking out rival fighters and battling them in spontaneous duels. At the end of the Survival Eleven, the Gundams which have made it through this elimination process are eligible to compete in the League Finals.