Try using search bar, I posted an entire backstory based on what I found out in the game.

I'll go search for it now.

Edit: I found it! Here it is:

The Spiral Knights were in there space ship, the Skylark, when the engines failed over Cradle. Every knight was sent into an escape pod and loss consciousness upon contact. The first ones to reawaken consisted of the fabled Alpha Squad, whose names can be found out in the modules that you collect from bosses, and the npcs that you see in Haven. The Strangers welcomed the knights and let them build their base of operation. They found the clockworks and started some explorations and found out that it's full of other worlds that rotate around in the clockworks. Scientists analyzed Cradle and found a ton of energy on the planet which emanated from the core. They theorized that the energy from the core can be used to repair the Skylark so they can be on their way. They sent the Alpha Squad into the clockworks to see what's at the core, but they never came back... Now all the newly awakened spiral knights must delve deep into the clockworks to find what is at the core and what happened to Alpha Squad.

About the gremlins, they were here before the Spiral Order. They are led by King Tinkizar and are divided into classes which consist of Tenderfoot (T1), Ironclaw (T2), Darkfang (T3), and the Crimson Order who are the only ones who see the king. The gremlins created most of the construct monsters and some of the clockwork levels. They are usually found taking apart some levels in their deconstruction zones.

Also, the rest of the thread is here: http://forums.spiralknights.com/en/node/12013