[1] The district elects five members to Lisburn and Castlereagh City Council and contains the wards of Ballyhanwood, Carrowreagh, Dundonald, Enler, Graham's Bridge and Moneyreagh.
[2] Castlereagh East forms part of the Belfast East constituencies for the Northern Ireland Assembly and UK Parliament.
It was created for the 1985 local elections, replacing Castlereagh Area B which had existed since 1973, where it contained seven wards (Ballyhanwood, Carrowreagh, Dundonald, Enler, Gilnahirk, Graham's Bridge and Tullycarnet).
The Gilnahirk and Tullycarnet areas were transferred to Belfast City Council, while Moneyreagh was gained from Castlereagh South.
2011: 4 x DUP, 2 x Alliance, 1 x Green 2014: 3 x DUP, 1 x Alliance, 1 x TUV, 1 x UUP 2011-2014 Change: TUV and UUP gain from DUP, Alliance and Green and due to the loss of one seat 2005: 5 x DUP, 1 x Alliance, 1 x UUP 2011: 4 x DUP, 2 x Alliance, 1 x Green 2005-2011 Change: Alliance and Green gain from DUP and UUP 2001: 4 x DUP, 1 x UUP, 1 x Alliance, 1 x Independent 2005: 5 x DUP, 1 x UUP, 1 x Alliance 2001-2005 Change: DUP gain from Independent 1997: 4 x DUP, 1 x UUP, 1 x Alliance, 1 x Independent Unionist 2001: 4 x DUP, 1 x UUP, 1 x Alliance, 1 x Independent 1997-2001 Change: Independent gain from Independent Unionist 1993: 3 x DUP, 1 x Alliance, 1 x UUP, 1 x UPUP, 1 x Independent Unionist 1997: 4 x DUP, 1 x Alliance, 1 x UUP, 1 x Independent Unionist 1993-1997 Change: UPUP joins DUP 1989: 3 x DUP, 1 x Alliance, 1 x UUP, 1 x UPUP, 1 x Independent Unionist 1993: 3 x DUP, 1 x Alliance, 1 x UUP, 1 x UPUP, 1 x Independent Unionist 1989-1993: No change 1985: 3 x DUP, 3 x UUP, 1 x Alliance 1989: 3 x DUP, 1 x Alliance, 1 x UUP, 1 x UPUP, 1 x Independent Unionist 1985-1989 Change: UPUP and Independent Unionist gain from UUP (two seats) 1985: 3 x DUP, 3 x UUP, 1 x Alliance