Captain John Primrose Hay (4 April 1878 – 5 December 1949) was Labour MP for Glasgow Cathcart.
Hay was born in Coatbridge and was educated at the Glasgow Free Church Training College, and the University of Glasgow. He became a lecturer in mathematics at Manchuria Christian College from 1906 to 1915, when he joined the Royal Garrison Artillery. He served in France for the remainder of World War I, becoming a captain.[1] He held the Chinese Order of Wen-Hu.
Hay was a supporter of the Labour Party, for which he stood in Glasgow Cathcart at the 1922 United Kingdom general election, winning the seat. However, he lost in 1923, and was defeated again in 1924 and 1929.