Seaham was created under the Representation of the People Act 1918 for the 1918 general election, comprising northern parts of the abolished South Eastern Division of Durham.
It was abolished for the 1950 general election under the Representation of the People Act 1948, with the bulk of its area moved into the new constituency of Easington.
[1] The history of this constituency, which incorporated a lot of the mining area of the eastern part of County Durham around Seaham, is of strong Labour Party support.
At the following general election, in 1922, Sidney Webb, an early socialist and author of the Labour Party's then-new constitution, was returned.
He was subsequently raised to the peerage; his successor as parliamentary candidate was Ramsay MacDonald, the leader of the Labour Party at the time.