In 1939, he was appointed chief ordnance officer for Northern Ireland, and from 1944 until 1950 he served as minister of education.
[1] Hall-Thompson suffered criticism from some Unionists for appearing to compromise with the Roman Catholic Church while in this position.
[3] In 1950, Hall-Thompson was appointed chairman of Ways and Means Committee and Deputy Speaker of the Northern Ireland House of Commons.
[1] At the 1953 general election, he was defeated by Norman Porter, an independent Unionist who had been an outspoken and stern critic.
[2] Samuel's son, Lloyd Hall-Thompson, later became an MP in Northern Ireland.