The Pathet Lao (Lao: , "Lao Nation") was a communist political movement and organization in Laos, formed in the mid-20th century. The group was ultimately successful in assuming political power in 1975, after the Laotian Civil War. The Pathet Lao were always closely associated with Vietnamese communists. During the civil war, it was effectively organized, equipped and even led by the Army of North Vietnam. They fought against the anti-communist forces in the Vietnam War. Eventually, the term became the generic name for Laotian communists.
The political movement of the Pathet Lao was called first the "Lao People's Party" (1955–1972) and later the "Lao People's Revolutionary Party" (1972–present).
Key Pathet Lao leaders include Prince Souphanouvong, Kaysone Phomvihane, Phoumi Vongvichit, Nouhak Phoumsavanh and Khamtay Siphandone.
The political wing of the Pathet Lao, called the "Lao Patriotic Front" (Lao: Neo Lao Hak Xat) served in multiple coalition governments, starting in 1956. Through the 1960s and 1970s the Pathet Lao battled the Royal Lao government during the Laotian Civil War, gaining control of the north and east of Laos. The Pathet Lao gained power throughout the country by the spring of 1975. In December, the US-backed Vientiane government fell and the Lao People's Revolutionary Party formed a new government.