 The pro-Treaty wing of Sinn Féin had decided to break off and become a distinct party in late December 1922, but its launch was delayed until after the New Year as a direct consequence of the turmoil caused by the Irish Civil War.The leadership of the pro-Treaty Sinn Féin in 1922 included Arthur Griffith, Michael Collins and W. T. Cosgrave.Cosgrave and Griffith had been prominent in Sinn Féin since the 1900s, while Collins rose quickly through its ranks after the 1916 Easter Rising.