In the year 2000, the Soltan Star Empire invaded Earth. In doing so, it sent several space-fairing battle cruisers to perform orbital bombardments of major cities and military bases. For the first several months of the invasion, the Soltan Cruisers remained safely in orbit, unopposed, that is until Earth's super-powered heroes and the combined forces of Earth's military powers joined forces and destroyed three in orbit and sent one hurtling down to Earth, the fleet's flagship, where it crash landed in the Sahara Desert. Although only a few hundred of the Soltan flagship's crew survived the devastating crash landing, so did several other beings in the ship...beings that were far from being allies or crew of the Soltan starship.
They were extremely dangerous intergalactic prisoners.
The Soltans intended to create a penal colony on Midway Island in the Pacific to house dozens of their most vicious prisoners to get them off their ship and as far away from the Soltan Star Empire's system and the prisoner's sphere of influence as much as possible. Sadly, the flagship that was carrying those prisoners was the one that crashed in the Sahara, releasing several of the worst alien criminals, despots, wanna-be emperors and murderous psychopaths onto Earth.
Within the first few hours after the crash, these galactic criminals joined forces and mutilated every single remaining Soltan survivor in and about the wreckage. When several rescue ships arrived with troops to secure the downed flagship, these same criminals obliterated them as well, leaving nothing but a swath of strewn and ripped apart Soltan bodies amidst the Sahara's desert sands.
When some of Earth's nomadic tribes arrived on site, they were tortured for information about Earth and the means by which to leave it. One of the most powerful despots amidst the criminals, a being who claimed himself to be "Galaxon", formed a pact with his fellow alien criminals; a pact to do whatever was necessary to get a spaceship and get themselves back to their own home-worlds and galaxies where they'd continue their previous activities...as well as destroy the Soltans once and for all.
This band of galactic miscreants cautiously agreed to their beneficial alliance and called themselves the "Galactic Expatriates".
In the first two months, these Galactic Expatriates worked together while struggling to cross the vast Sahara Desert in what eventually led them to a nearby space launch center and take one of Earth's "interstellar" space ships and travel back to their home worlds. The promise to take them back to their own homeworlds was an empty gesture on the part of Galaxon; he had no intention of bringing them home, he instead needed to use his fellow expatriates long enough to get back into space and on his way back to Solta so that he could destroy it personally.
Little did Galaxon know that, at the time, Earth was barely able to go to the moon; interstellar travel didn't even exist yet except for space probes and those alone would need to travel nearly a decade before they'd reach the next star system.
The first location the Galactic Expatriates arrived at was the Jabal Hamzah ballistic missile test and launch facility in Egypt.
There, after decimating nearly all the facility's military forces in less than a half hour, they realized that their desired "interstellar spacecraft" were merely suborbital rockets...test dummies, at that. Furious, Galaxon and his crew destroyed the site and killed every living person at the facility. Before they killed the last person there, they forced one of the site's lead engineers to find them a suitable space launch facility on Earth capable of interstellar travel. When the engineer told him there was no such place on Earth, Galaxon was once again displeased. After getting a printout and a deciphered map of each rocket launch location on Earth, the beleaguered expatriates slowly made their way to one of the most out of the way locations they could find and attempt to build their own interstellar ship - Omalek Island of the Marshall Islands in the Pacific Ocean.
Several months later, the expatriates finally made their way to the island, bringing with them a treasure trove of materials, components and equipment they'd need to build their ship...including human slave labor. They took over Omalek is mere minutes and set up operations to build their ship, adding the people living on Omalek as additional slave labor. Since Earth was still in the through of chaos and rebuilding after defeating the invading Soltans (which occurred in late 2000), Omalek was but a passing thought to most.
By 2003, the US Government decided to do a reconnaissance of Omalek to find out what they believed was a Soltan attack that had destroyed the entire island's populace and facilities, only to find a massive spaceship being built there instead. The US government sent a US Navy SEAL team in to recon the island, but were attacked by the expatriates and killed. Next, the US Navy was sent in. Using a newly rebuilt aircraft carrier and warplanes, they flew to the island to destroy the ship. They did destroy the ship's storage location for all the engine fuel, but did little to no damage to the rest of the facility, due in fact to the expatriates destroying all of the attacking warplanes. Next was an offshore missile and gunnery bombardment. Each of those ships also met a similar fate, losing over five warships (including the aircraft carrier) and over 300 sailors and airmen. With the United States' military forces depleted and not wanting to loose anymore warships and planes, the United States turned to the United Nations and access to G.U.A.R.D.
GUARD spent a month defining a plan of attack on the expatriates. Knowing they needed more fuel to replenish that lost during the previous attacks, they bailed a trap on an uninhabited island a few hundred miles away. Half of the expatriates went to the island, along with over 100 slave human workers, to retrieve the needed fuel. Once there, the trap was sprung and that half of the expatriates was captured and imprisoned in an old secretive super-powered detention facility on Midway Island, a few hundred miles west of Hawai'i. When Galaxon and the remaining expatriates realized what happened, they went on a destructive tirade across the Marshall Islands, killing hundreds in their wake and destroying any building or home, all the while demanding the release of their fellow expatriates and the delivery of the fuel...or else there'd be more bloodshed and destruction.
After several more attempts to corral and detain the remaining expatriates, GUARD decided to create Operation: Trojan. Inside the tanker filled with the requested engine fuel for their spaceship, they placed several powerful explosives that when set off, would create an explosion that would wipe out everything in a 3 mile radius of the tanker. As a backup plan, they also planned on nuking the island with a tactical nuke, but since the island had innocent slave-bound people on it, it was only considered as a last resort. Because both of these plans involved a potential for civilian deaths, GUARD threw together a team of scientists, engineers and troops led by Vladimir Vorisch, the hero of Russia during the Soltan Invasion and came up with an alternate plan to defeat them.
On the day Operation: Trojan was enacted, Galaxon knew it was a blatant trap. He instead blew up the tanker himself and told them they only had hours left before the expatriates were to unleashed their death and destruction. The US government authorized the nuclear attack, but Vorisch instead implemented his alternate plan, hoping it'd work before the island would be nuked. Vorisch's plan: illegally gather the several thousand captive Soltans in custody and send them into battle against the expatriates to earn a free ticket to where the Soltans had since set up shop - the far side of Mars. Using hacked federal authority codes and GUARD's hypersonic VTOL transport fleet, Vorisch did just that. After explaining to them that defeating the expatriates would garner their freedom (which Vorisch wasn't authorized to do), the Soltans were more than happy to fight the expatriates (seems they had a greater hatred of the Expatriates than the Terrans). In a massive assault, the Soltans, given their own previously locked-away weapons, swarmed the expatriates. During that same time, Vorisch and his men collected up all the human slaves on the island and flew them to safety. As the nuke was only 130 miles from Omalek Island, Galaxon, the last standing expatriate, fell to the Soltan swarm. The nuke was aborted in mid flight and splashed down only a dozen or so miles from the island, inert and safe. With only several hundred Soltans remaining, the Galactic Expatriates were defeated.
For the next several years, the remaining Soltans were allowed to live on the island and were provided the food and resources they needed to finish building a rocket that would take them to Mars, much to the chagrin of GUARD's director and the United Nations. Nonetheless, in 2010, the Soltans finally finished their rocket, boarded it, and blasted it off to Mars. They were last seen entering Mars' orbit in 2012, never to be seen again. As for the Galactic Expatriates...
All of the Galactic Expatriates lived to see another day, but were placed in the most powerful restraints ever devised at a prison facility on the Moon at GUARD's newly built Fort Armstrong, run by Moonguard. There, the Galactic Expatriates remained imprisoned...until 2013. That's when they broke out, commandeered a shuttle and took over an unknown secret Chinese space station.
After weeks there, the Galactic Expatriates left the station, launching the station's escape pods and blowing up the station in their wake. The escape pods were found in the Amazon River Basin in Brazil. Between then and now, there have been several incidents of the Galactic Expatriates, mostly independently, creating their own brand of thefts, murders and chaos in and around South America. No one has been able to capture them in recent times. Several months ago, though, they were all seen together once again, in an attempt to steal a rocket from the launch pad at the Brazil Space Agency's Alcântara Launch Center, Maranhão site. Thanks to a few incredible superheroes though, their attempt was fully thwarted.
Today, the Galactic Expatriates are still on the loose on Earth. They are known to not be happy working with each other again after their summary defeat at Omalek Island and have instead gone and done many independent acts of aggression against the people of Earth. Recent intelligence, however, indicates that the expatriates are starting to work together again towards a new twist on their original plan - to get back to their home worlds, this time, even if it means the destruction of Earth in the process...
This band of galactic despots and villains have proven one thing: they want to either take over Earth or find a way home. They fight continuously amongst themselves, but always recombine their efforts to reach one of their two previously listed goals. All of them and severely dangerous individually; combined, they are a danger that one day Earth may not be able to stop.