In March 2005, he defeated his former friend Red Vinny, Vid Vain and The "Pukka One" Darren Burridge to become the first ever IWW International champion...
This led to a feud with Darren Burridge, which involved "The Pukka One" interfering in Sheamus' championship match against D'lo Brown by hitting Sheamus in the head with a baton, thus giving D'lo the victory and IWW International championship.
SOS and Burridge squared off in a grudge match which resulted in SOS getting his revenge and the victory. Sheamus then set his sights on winning his title back and defeated both Red Vinny and Vic Viper to win the no.1 contendership match against D'Lo Brown and The Assassin at a MEW show in Newcastle in October 2005.
SOS persevered and pinned D'Lo to become a two time IWW champion and brought the title back to Ireland. In his latest match at the IWW Supershow in the SFX in November 2005, SOS defeated the legendary Vampiro in a no-disqualification match, to cement his position as Ireland's top professional wrestler.