The MechWarrior PC gaming franchise is all about giant stompy robots in a high-tech setting where humanity has conquered the stars and interstellar nations have taken form. These games feature advanced controls and deeply customizable weapons systems, but there's more to it than sheer carnage. The franchise's lore is deep, and that lore is centered on all-out war.
While the five great noble houses of the Inner Sphere (general human space) were fighting each other for supremacy, there was a second, hidden civilization deep in unknown space: the terrifying warrior Clans. These people were ready to conquer the Inner Sphere, and their attempted invasion changed the lore forever. Many of the PC games are based on the aftereffects of that historic invasion.
How the MechWarrior Clans Launched Their Invasion
By the year 3048, the warrior Clans were ready to attack the Inner Sphere realm and its many worlds, despite some political differences among the Clans. In 3049, the invasion fleet was assembled and departed Clan space, arriving at the Inner Sphere's peripheral worlds. Once the Clans gained a foothold there and earned an alliance with the ComStar organization, they launched their invasion in full in March 3050.
At this point, the Clans had a few key advantages: the incredible skill and bloodlust of their 'Mech pilots and soldiers, their highly advanced weapons and 'Mechs, and (most of all) the element of surprise. Despite being greatly outnumbered, the Clans invaded anyway, taking many worlds from the Lyran Commonwealth, the Free Rasalhague Republic and the Draconis Combine. By October, the Clans captured over 200 planets, suffering few defeats against the technologically inferior defenders (with the battles of Twycross and Wolcott being exceptions).
However, the Clans were slowing down. They restrained themselves through honor rules, while the Inner Sphere's defenders did not. The Clans underestimated their admittedly barbaric and crude opponents. In October 3050, after an intense space battle, the Clans' overall leader ilKhan Leo Showers was killed, and the Clans retreated home to elect a new leader, leaving behind garrison forces on their captured worlds.
The invasion was starting to go sour, since the Clans' leaders had arrogantly concocted a simplistic plan and didn't bring enough supplies for the campaign. They expected a quick and easy invasion, but the war was becoming a slog, and the Clans weren't ready for such a grind. They resumed the invasion in November 3051 with a few more Clans in tow, capturing many more worlds with great effort.
Then, ComStar, which had its own secret army, turned on the Clans at last. The seven invading Clans and the ComStar army fought a proxy battle for the fate of Earth itself, and ComStar won. The Clans agreed to a 15-year truce, halting the invasion in its tracks. However, the Clans kept their conquered worlds and made plans to someday take more, including Earth, something the united Inner Sphere states hopes they'll never achieve.
The Clan Invasion's Aftereffects in the Lore & Games
The Clans took many worlds by force, especially the strong Clan Wolf and the methodical Clan Ghost Bear, but the invaders failed to take Earth, their primary objective. The goal was to put Earth in Clan hands and restore the great Star League from generations past, reuniting the fractured Inner Sphere under Clan law. The Clans were born from the remnants of the Star League when it fell, and they saw Earth as their birthright. That dream died in 3052 during the Battle of Tukayyid, but the Clans didn't leave the Inner Sphere. Instead, the Clans and the great nations learned to become uneasy neighbors.
The Clans feuded with the Inner Sphere states here and there, with Clan Jade Falcon and Clan Smoke Jaguar being the most antagonistic. Overall, though, the invading Clans learned to blend their odd way of life with that of the Inner Sphere, especially Clan Ghost Bear, though the Smoke Jaguars were wiped out entirely in 3059-60 as revenge for the invasion.
The invading Clans became geographically and politically distinct from the remaining Clans back in home space, and that rift deepened as time went on. The invader Clans designed new 'Mechs and tanks with Inner Sphere opponents in mind, and even borrowed design philosophies from them. By some point, Inner Sphere armies were making use of Clan 'Mechs and weapons designs themselves -- that is, when they could afford such tech.
MechWarrior 2 demonstrates the political divide between Clans Jade Falcon and Wolf, where the Falcons supported the original invasion and the Wolves didn't. They came to blows over it in 3057, fighting each other on the Inner Sphere planets that they had conquered years earlier. Meanwhile, MechWarrior 3 thrusts the pilot into the heat of battle against Clan Smoke Jaguar, chasing them back to their homeworlds and destroying them as retaliation for the invasion earlier. Additionally, players can use both Clan and Inner Sphere 'Mechs.
MechWarrior Online is a multiplayer-only game that features both Clan and Inner Sphere 'Mechs and weapons, and a 12-player team can include 'Mechs from both factions fighting side by side, from the Mad Cat and the Thor to the Atlas and Dragon. In MWO, the Clans and Inner Sphere nations have finally come together like never before.