The Ulster Protestant League (UPL) was an anti-Catholic supremacist loyalist organisation in Northern Ireland. The organisation was established in 1931 by a group inspired in part by the example of the Scottish Protestant League. It initially had some links with the Ulster Unionist Party (UUP), and UUP members such as James Hanna McCormick attended its meetings. The UPL remained active until the start of World War II. During the late 1930s, it organised in support of Franco's Nationalists in the Spanish Civil War, and organised heckling at socialist meetings.