The railroad brotherhoods are labor unions of railroad workers in the United States. They first appeared in 1863 and they are still active. Until recent years they were largely independent of each other and of the American Federation of Labor.

With the rapid growth and consolidation of large railroad systems after 1870, union organizations sprang up, covering the entire nation. By 1901, 17 major railway brotherhood were in operation; they generally worked amicably with management, which recognize their usefulness.^[1] Key unions included the Brotherhood of Locomotive Engineers (BLE), the Order of Railway Conductors, the Brotherhood of Locomotive Firemen, and the Brotherhood of Railroad Trainmen.^[2] Their main goal was building insurance and medical packages for their members, and negotiating bureaucratic work rules that favored their membership, such as seniority and grievance procedures.^[3] They were not members of the AFL, and fought off more radical rivals such as the Knights of Labor in the 1880s and the American Railroad Union in the 1890s. They consolidated their power in 1916, after threatening a national strike, by securing the Adamson Act, a federal law that provided 10 hours' pay for an eight-hour day.^[4][5]

At the end World War I, the brotherhoods promoted the "Plumb Plan" for the nationalization of the railroads, and conducted a national strike in 1919.^[6] Both efforts failed, and the brotherhoods were largely stagnant in the 1920s. They generally were independent politically, but supported the third-party campaign of Robert M. La Follette in 1924.

The Republican Party was dominant in Washington and it was generally hostile to the brotherhoods until it moderated its position around 1926.^[7]

The Great Railroad Strike of 1922, a nationwide railroad shop workers' strike, began on July 1. The immediate cause of the strike was the Railroad Labor Board's announcement that hourly wages would be cut by seven cents on July 1, which prompted a shop workers' vote on whether or not to strike. The operators' union did not join in the strike, and the railroads employed strikebreakers to fill three-fourths of the roughly 400,000 vacated positions, increasing hostilities between the railroads and the striking workers. On September 1, a federal judge issued a sweeping injunction against striking, assembling, picketing, colloquially known as the "Daugherty injunction".

Unions bitterly resented the injunction; a few sympathy strikes shut down some railroads completely. The strike eventually died out as many shopmen made deals with the railroads on the local level. The often unpalatable concessions—coupled with memories of the violence and tension during the strike—soured relations between the railroads and the shopmen for years.

• Brotherhood of Railway Clerks
• Labor history of the United States § Railroad brotherhoods