The Christmas Uprising, also known as the Christmas Rebellion, was a failed uprising in Montenegro led by the Greens in early January 1919. The military leader of the uprising was Krsto Popović and its political leader was Jovan Plamenac.

The Greens were a group of loyalists of King Nikola of Montenegro. They originated from the members of the True People's Party and were most notable for instigating the Christmas Uprising of 1919. The rebellion was staged in an attempt to prevent the dethroning of the Petrović-Njegoš dynasty and the subsequent integration of Montenegro into the Kingdom of Yugoslavia. The Greens were supporters of the House of Petrović-Njegoš, which once the house was dethroned after World War I, led the Greens to fight for the establishment of Montenegro as a province within the Yugoslav kingdom. Following their defeat in the Christmas Rebellion, the Greens continued on with their guerrilla warfare until 1929. The motto of the movement was "For the Right, Honour and Freedom of Montenegro".