In 1819, to break this impasse Bolívar invaded New Granada, which had been reconquered by Morillo's expeditionary force three years earlier. Bolívar decisively defeated the royalists at Boyacá. With the liberation of New Granada, the republicans had a significant base from which to attack Morillo's forces. A republican Congress at Angostura (today Ciudad Bolívar), which already had a small New Granada delegation, declared the union of New Granada and Venezuela in a Republic of Colombia (the Gran Colombia of contemporary accounts) to present a united front against the Spanish Monarchy.