The Republic of the Rif was a confederate republic in the Rif, Morocco, that existed between 1921 and 1926. It was created in September 1921, when a coalition of Rifians led by Abd el-Krim revolted in the Rif War against the Spanish protectorate in Morocco. The French would intervene on the side of Spain in the later stages of the conflict. A protracted struggle for independence killed many Rifians and Spanish–French soldiers, and witnessed the use of chemical weapons by the Spanish army—their first widespread deployment since the end of the World War I. The eventual Spanish–French victory was owed to the technological and manpower advantages despite their lack of morale and coherence. Following the war's end, the Republic was ultimately dissolved in 1926.

The Rif or Riff, also called Rif Mountains, is a geographic region in northern Morocco. It is bordered on the north by the Mediterranean Sea and Spain and on the west by the Atlantic Ocean, and is the homeland of the Rifians and the Jebala people. This mountainous and fertile area is bordered by Cape Spartel and Tangier to the west, by Berkane and the Moulouya River to the east, by the Mediterranean to the north, and by the Ouergha River to the south. The Rif mountains are separated into the eastern Rif mountains and western Rif mountains.