McSparran was born in Glasgow to an Irish family[1] He studied at St Mungo's Academy, Glasgow, then St Malachy's College in Belfast, Queen's University of Belfast, and the National University of Ireland.
[3] At the 1945 Northern Ireland general election, McSparran was elected for the Nationalist Party in Mourne: during his own campaign McSparran emphasised the need for northern nationalists to unite to help themselves, as well as promoting their aim to end partition.
In 1953, he became instead the President of the League, and in 1958, he stood down from Parliament and his position as Chairman of the Nationalist Party in order to concentrate on his legal career.
[2] McSparran remained active as a barrister and supported the Northern Ireland Civil Rights Association.
[4] McSparran had, through his Antrim roots, deep connections with many prominent Catholic families with clerical links and business interests.