The Faction was created by Klaus and in the past it was made up of pirates and dirty politicians.
InFruit of the Poisoned Tree, Niklaus Mikaelson goes to them while they're in middle of a meeting to asks for their resources to find Agnes and makes mention to Kieran that she is the one responsible for Sean losing his mind which eventually lead to murder-suicide in the church. Kieran agrees only because he wants to deal with Agnes herself.
In Reigning Pain in New Orleans, Everyone (except Kieran), puts a hit out on vampires as a warning to the new king Klaus. Marcel and Klaus kill every member (except Kieran) who tells them some were important members of the community and people would question their sudden deaths. Klaus tells Kieran they're are easily replaceable and orders him to get new trustworthy members.
In Moon Over Bourbon Street, Elijah revamps The Faction, with a new peace treaty, with it now including 1 member of each of the 4 species that live in New Orleans.