 The constant growth of influence and prestige of the Federal League frightened the Luso-Brazilian Monarchy (because of its republicanism), and in August 1816 they invaded the Eastern Province, with the intention of destroying the protector and his revolution.The Luso-Brazilian expeditionary force, thanks to their material superiority and military experience and organization (including in part its European warfare experience), occupied Montevideo on 20 January 1817, and finally after a struggle for three years in the countryside, defeated the pro-Artigas forces in the Battle of Tacuarembó.In 1821, the Provincia Oriental del Río de la Plata (present-day Uruguay), was annexed by the Portugal into the Brazilian territory (Brazil was a Portuguese territory at that time) under the name of Província Cisplatina.