The 1952 Belfast South by-election was held following the resignation of Ulster Unionist Party (UUP) Member of Parliament, Hugh Gage.
[1] Belfast South had consistently elected UUP members since its recreation in 1922, and no Irish nationalist had even stood in the seat in that period.
The CWLP had merged with the UUP in 1947, so by the 1950 general election, Gage was able to take three-quarters of the vote, the rest going to a NILP opponent.
[1] The UUP selected David Campbell, while the NILP opted to stand their party secretary, Sam Napier.
Campbell easily won the seat, taking more than three-quarters of the votes, in a near repeat of the result of the two previous general elections.