DC Comics' Legion of Super-Heroes fights evil and oppression a thousand years in the future, when beings from across the stars have come together in peace and harmony. Accordingly, the Legion and their allies operate under the good graces of the United Planets, an intergalactic government which, for most of its existence, has been headquartered in the venerable Earth city of Metropolis.
If that reminds you of Star Trek's United Federation of Planets, which was founded in 2161 with its capitol in San Francisco, we're not surprised. However, the Legion debuted in April 1958's Adventure Comics #247, well ahead of Trek's premiere on September 8, 1966. Indeed, the first reference to a "United Planets" appears to have been in January 1966's Adventure Comics #340, where we see Brainiac 5 working in a United Planets laboratory.
Thanks to the upcoming Legion miniseries Millennium, DC readers are about to travel through centuries of future history, from Kamandi's Great Disaster to the Neo-Gotham of Batman Beyond and ... well, beyond. Along the way we may very well learn new details about how the United Planets helped create the Legion's future, but now, we're piecing together what we already know.
A Legacy of Valor
Traditionally, the history of the United Planets begins in the 20th Century, with the heroic career of Lar Gand. As a native of the planet Daxam, Lar gained Kryptonian-style super-powers under the rays of a yellow sun; but his vulnerability was to the element lead instead of Kryptonite. After the events of 1988's Invasion! miniseries, Lar left Daxam and became the superhero called Valor.
Operating throughout the galaxy both solo and as a member of the Licensed Extra-Governmental Interstellar Operatives Network, or L.E.G.I.O.N., Law was eventually banished to a limbo-type dimension for a thousand years, and that whole complicated story was told in Valor #12-21, October 1993-August 1994. However, as related in November 1991's Legion of Super-Heroes Annual #2, written by Tom & Mary Bierbaum and penciled by Brandon Peterson, by that time he had already rescued thousands of humanoids from a Dominator prison camp. The Dominators' experiments had given a number of them super-powers, so when they were freed, their descendants helped found a number of future United Planets worlds.
The 25th Century
After that things get a little murky, but we can start to pin things down in the 25th Century. Both the Reverse-Flash and the Space Museum hail from this period, with the former first appearing in September 1963's The Flash #139 and the latter debuting in May 1959's Strange Adventures #104. Gardner Fox co-created both, along with artists Carmine Infantino (Reverse-Flash) and Mike Sekowsky (Space Museum). We'll see the Space Museum in the Millennium miniseries, as part of the backstory of Booster Gold.
The 25th Century of the Reverse-Flash and Space Museum is a typically antiseptic future setting, with gleaming architecture and no apparent societal worries. However, in October 1998's Chronos #8, written by John Francis Moore and penciled by Paul Guinan, time-traveler Walker Gabriel finds that the Metropolis of 2452 has been devastated by a Khund invasion. Wondering why the immortal Superman hadn't defeated the extraterrestrial forces, Walker learns that the "United Planets Alliance" repelled the invaders instead. Clearly this is a precursor to the Legion's UP, but it may not have been the real thing just yet.
World War VI and the 30th Century
Another clue that Earth might not have been part of an actual, factual United Planets comes in August 1975's Superboy #210. There, the Legion meets a soldier newly awakened from the year 2783, when he fought in World War VI, perhaps as part of the "Great Wars" of the 28th Century, which were referenced in March 1991's Legion of Super-Heroes #16. WWVI nevertheless seems like the kind of thing that wouldn't have happened if Earth been part of an interplanetary union; and would have encouraged such a union to form. (Similarly, the one-two punch of the 1990s Eugenics Wars and the 21st Century's World War III helped lead to Trek's united Earth government.)
Accordingly, while we couldn't find a precise date or rationale for the United Planets' formation, we know it happened no later than the 29th Century. This is because the UP's main law-enforcement arm, the Science Police, had been around for "nearly a century" as of 2988, according to September 1988's Who's Who In the Legion #5, which lists the Science Police's first appearance as September 1962's Adventure Comics #300.
In any event, the Science Police officers have been an integral part of the series ever since, working closely with the Legionnaires despite the occasional jurisdictional dispute. In fact, to invoke Star Trek yet again, the Science Police would be a pretty close analogue to Starfleet. Therefore, imagine your favorite Federation officers having to deal with a group of planet-hopping teenage superheroes.
Famous Faces and Places
The most powerful body in the United Planets government is the United Planets Inner Council, made up of chief executives from several worlds, including the President of Earth, as seen in comics like October 1966's Adventure Comics #349. Regardless, one of the UP's most influential figures isn't a politician; but René Jacques "R.J." Brande, the richest man in the universe and the Legion's biggest supporter. Created by E. Nelson Bridwell and Curt Swan, Brande first appeared (unnamed) in November 1966's Adventure Comics #350. While he was killed in October 2008's Final Crisis: Legion Of 3 Worlds, we're almost certain to see him, or his influence, again in the new Legion series.
Brande can be counted on to clash with the UP leadership, including the President of Earth; who for years was Colossal Boy's mother Marte Allon. Brande also had his own Flintheart Glomgold in the person of ruthless businessman Leland McCauley.
The United Planets includes too many worlds to list here, but the most notable include the prison planet Takron-Galtos, which houses the Legion's deadliest foes; the artificial planet Weber's World, which has also served as the UP's capital; the planetoid Shanghalla, a cosmic memorial to Legionnaires and others who have made the ultimate sacrifice; and Sorcerer's World, for all your magical needs.
While the United Planets strives to uphold the ideals of unity and diversity, things haven't always been rosy. Paul Levitz and Chris Batista's Legion: Secret Origin miniseries (December 2011-May 2012) sets the group's early days just after a cosmic schism called "the Sundering," and the "5 Years Later" version of the team which started in 1989 saw the UP rebuilding following the devastating Magic Wars. Nevertheless, we're sure that Brian Michael Bendis, Ryan Sook and their collaborators will have much to say about the history and structure of the United Planets.