After the destruction of Genosha by Cassandra Nova, and the virtual elimination of its mutant population, Charles Xavier moves to Genosha to help the survivors rebuild. Charles quickly located several surviving mutants, and the first of his new team in discovering Wicked and Freakshow. The group then discovers Magneto who had been laying low on Genosha, not knowing of the attack on New York by an impostor, as well as Callisto who was going to kill Magneto. Freakshow summoned spirits of the Genoshan dead and prevented Callisto from killing Magneto.
A Magistrates ship crashing down on Genosha carried the captured bodies of both Shola Inkose and the Prime Sentinel Karima Shapandar. Shola was expelled, and Karima's body was thrown into the ocean. Despite her Sentinel nature, Charles Xavier saved her. Together, Xavier and Magneto were able to free her mind from her Prime Sentinel programming.
The team then found Broadband and Book, as well as Dark Beast. Xavier offered Dark Beast a sort of amnesty in exchange for assisting them, which McCoy accepted.
Excalibur were created Chris Claremont and Aaron Lopresti and first appeared in Excalibur #1 in 2004. Interestingly, Claremont was also the created of the British superhero team of the same name who are entirely unconnected to this team.
This Excalibur team were short-lived, soon being replaced by book called New Excalibur (again by Claremont) which took the Excalibur name back to Britain and had no relationship to the Genoshan Excalibur.
Major Story Arcs
House of M
The team was in the process of restoring Genosha when the Magneto's daughter, the Scarlet Witch, went insane and destroyed the Avengers. Magneto hears her psychic cry for help and uses his power to create a wormhole and rescues his daughter. Magneto becomes reclusive and withdrawn, focused only on his daughter. Xavier and Magneto continue to try to help Wanda, who remains in stasis. These are some of the main events leading up to the House of M.
After M-Day the team is effectively gone. While many of the members remained on Genosha, they are de-powered and Xavier is nowhere to be found. Magneto remains on the island, but also being de-powered is more depressed and withdrawn than ever. Quicksilver brings the Inhumans' Terrigen Mists to the island, and causes even more damage by granting powers back to several of these mutants to a level that they are completely unable to control rendering Unus dead by his own force field, Freakshow unable to return to human form, Callisto in a coma by the level of which her senses are heightened, and Wicked no longer in control of the energies of the dead but instead haunted by them.
Members of the Genoshan Excalibur include: Charles Xavier, Magneto, Callisto, Karima Shapandar, Shola, Wicked, Freakshow, Dark Beast, Broadband, and Book.