On the 15th of February, 1819, congress was installed at Angostura. The supreme chief pronounced an eloquent discourse, and resigned his authority. Congress immediately, and unanimously, elected him president of the republic.
Early in March, the president rejoined the army, which was very much reduced by sickness. On the 27th, he defeated the vanguard of the Spaniards. Adopting a desultory system of warfare, he obliged them to recross the Apure, having lost half their original numbers.
While Morillo remained in winter quarters, the president traversed the vast plains of the Apure and Casanare, which are rendered almost impassable by inundations from the month of May to the end of August. In Casanare, the president formed a junction with the division of Santander, two thousand strong. Santander had, from the commencement of the revolution, dedicated himself with enthusiastic constancy to the cause of his country. He now expelled the Spaniards from their formidable position of Paya, and opened the way for the president to cross the terrific Andes, in effecting which, nearly a fourth of his army perished from the effects of cold and excessive fatigue.
On the 11th of July, the president attacked the royal army at Gamarra. After a long engagement, the Spanish general Barrero retired, and did not again offer battle, except in positions almost inaccessible. Bonza was invested by the patriots for some days in sight of both armies. The president, by a flank movement, brought the Spaniards to action on the 25th of July, at Bargas. The Spaniards, though superior in numbers, and advantageously posted, gave way, and the president obtained a complete victory. His inferior forces, however, and the nature of the country, did not allow him to make the most of this glorious success; but he obtained a thousand recruits, and marched to interpose between the defeated Barrero and the viceroy Samano, who, with all the disposable force south of Bogotá, was about to support Barrero. The result of the president's daring and masterly movement was the battle of Boyaca, fought on the 7th of August, and which has been called the birth of Colombia. In this battle, the English troops, under the command of Major Mackintosh, greatly distinguished themselves. The gallant major was promoted by the liberator on the field. In three days afterwards the president entered Bogotá in triumph, and, within a short period, eleven provinces of New Granada announced their adhesion to the cause of independence.
Bolivar repaired to Angostura, where he once more resigned his authority to the representatives of the people, and laid on their floor the trophies of the last campaign. On the 25th of December, 1819, congress, at the suggestion of the president, decreed that thenceforth Venezuela and New Granada should form one republic, under the denomination of COLOMBIA. At the same time it conferred upon Bolivar the title of LIBERATOR OF COLOMBIA, and re-elected him president of the republic.
In March, 1820, he arrived at Bogotá, and occupied himself until August in the organization of the army cantoned at various points between Cucuta and San Fernando de Apure.
The Spanish revolution, which originated in the Isla de Leon, inspired the South Americans with new hopes. These were raised still higher by the solicitude of Morillo to negotiate an armistice; but Bolivar, refusing to treat upon any other basis than that of independence, marched to the department of the Magdalena, reviewed the besieging force before Carthagena, and reinforced the division of the south, destined to act against Popayan and Quito. The president drove the Spaniards from the provinces of Merida and Truxillo, and established his winter headquarters at the latter town. On the 26th of November, the president concluded an armistice of six months with Morillo, who engaged that, on the renewal of hostilities, the war should be carried on, conformably to the practice of civilized nations.
In the beginning of the year 1821, the liberator went to Bogotá, to attend to the affairs of the south; when hearing of the arrival at Caracas of Spanish commissioners to treat for peace, he returned to Truxillo; but no terms were then agreed upon. In the meanwhile, the province of Maracaybo shook off the Spanish yoke. Morillo having departed for Europe, General La Torre, a brave and very superior man, succeeded to the command of the royal army, and made strong remonstrances against the movement in the province of Maracaybo, which he deemed an infraction of the armistice, and hostilities in consequence recommenced. The liberator concentrated his forces in Varinas; he detached a division to the coast under General Urdaneta, and another to the east, under General Bermudez, to divide the attention of the enemy, and marched himself against Caracas. On the 24th of June, the liberator attacked and defeated the Spaniards, who had taken up a strong position at Carabobo. The numbers on both sides were nearly equal. This battle decided the fate of Colombia. The victorious liberator entered Caracas on the 29th. On the 2nd of July, La Guayra also surrendered to him.
Leaving a besieging division before Puerto Cabello, the liberator went to Cucuta, where he resigned once more the office of president of the republic, which, in admiration of his disinterestedness, instantly re-elected him.
When the province of Guayaquil declared itself independent, it solicited the assistance of Bolivar against the Spaniards in Quito. A small division was accordingly sent there.