In 1801 the first Afro-Argentine militias were organised, under the auspices of the Compañía de Granaderos de Pardos libres de Buenos Aires and Compañía de Granaderos de Morenos libres de Buenos Aires. The pardos were free people of mixed European, African, and Native American, particularly Guaraní, descent, whereas the "morenos" seem to have been composed of soldiers of largely African ancestry. These forces were unified into the Batallón de Pardos y Morenos, also known as the "Batallón Castas", at a strength of 9 companies, plus 4 auxiliary slave companies, at the time of the first British invasion of the Rio del Plata. Regimental status was gained in 1810, and the new "Regimento de Pardos y Morenos" participated in the Argentine War of Independence.