In 1977 twenty-four Stó:lō First Nations banded together to sign the Stó:lō Declaration and creating the Stó:lō Nation Chiefs Council. By 1995 when the BC Treaty Process started three First Nations had left the Sto:lo Nation.[2] By 2005 two more nations had left leaving 19 First Nations.
In 2005, these 19 Sto:lo First Nations that remained in the Sto:lo Nation underwent an internal re-organization, eventually forming two tribal councils. Eleven of these First Nations stayed in the Sto:lo Nation Chiefs Council: Aitchelitz, Leq'a:mel, Matsqui, Popkum, Shxwhá:y Village, Skawahlook, Skowkale, Squiala, Sumas, Tzeachten, and Yakweakwioose.[2]