The Gerard O' Callaghan Sinn Féin Cumann held its' inaugural meeting on Tuesday 22nd September 1998 in Tullysaran. It was decided at this meeting to name the newly formed Cumann after Óglach Gerard O' Callaghan, East Tyrone Brigade Óglaigh na hÉireann. The Cumann is based in the Orchard Ward of Armagh City & District Council Area and has 10 members, including Sinn Féin Councillor Paul Corrigan who was elected onto Armagh City & District Council in 2001. Always active in their political and electoral work, the Cumann members have also been behind many initiatives to promote Irish Republicanism within their local communities and the Cumann has always been well represented at National and Local commemorations throughout Ireland. In 2005, the new Cumann banner was launched and carried for the first time at the Céad Bliain / Sinn Féin 100 'Make Partition History March for Irish Unity' in Dublin

The Gerard O' Callaghan Sinn Féin Cumann banner was officially launched in December 2005. The basic design of the banner was created by the members of the Gerard O' Callaghan Sinn Féin Cumann, Tullysaran. The banner itself was made in Dublin and was carried in public for the first time at the 'Make Partition History' National March through Dublin on September 24th 2005 to mark the 100th anniversary of Sinn Féin (1905 - 2005). Then, in December 2005, the banner was officially launched at a function held in Armagh City and since then has been carried at the National and local commemorations throughout Ireland, from Armagh and Belfast, through the streets of Derry and from Dublin to Cork.