Historians use the name Third Republic of Venezuela to refer to the period from about 1817 to 1819, when a rump government, organized by Bolívar began functioning in the Venezuelan Llanos. The year before, various Venezuelan guerilla forces managed to permanently establish themselves in the Llanos and captured the city of Angostura, which became their headquarters. This period culminated with the formation of the Congress of Angostura in 1819, which wrote a new constitution for Venezuela, replacing the one from 1811, which in theory, was still valid, although suspended since the collapse of the first republic in 1812.