Catholic League

• Catholic League (French), created by Henry of Guise, in 1576 during the French Wars of Religion
• Catholic League (German), a confederation of Catholic German states formed to counteract the Protestant Union
• Catholic League (U.S.), a Roman Catholic civil rights organization in the United States
• Catholic League (Anglican), an organisation to promote reunion of the Church of England and the Holy See

In sports:

• Philadelphia Catholic League, a high school sports league composed of 20 Catholic High Schools in and around Philadelphia
• Baltimore Catholic League, a competitive basketball association composed of private Catholic high schools in the Baltimore, Maryland area
• New Orleans Catholic League, a high school athletic league in the New Orleans, Louisiana area