Prohibition Party, oldest minor U.S. political party still in existence. It was founded in 1869 to campaign for legislation to prohibit the manufacture and sale of intoxicating liquors, and from time to time has nominated candidates for state and local office in nearly every state of the Union. Rural and small-town voters affiliated with Protestant evangelical churches provided most of the party’s support. The Prohibition Party reached the peak of its national strength in the elections of 1888 and 1892, in each of which its candidate for president polled 2.2 percent of the popular vote. After 1900 its strength was effective mainly on the local and county levels.