Army of the North
The offensive operations started in 1810 and ended in 1817, with the defeat of the forces commanded by Gregorio Aráoz de La Madrid at the Battle of Sopachuy, the last attempt to advance into Upper Peru.
Since then, only defensive operations on the Northern frontier were carried on, as the offensive had been transferred to the Army of the Andes, commanded by José de San Martín, who devised the strategy of reaching the main royalist stronghold, Lima, through Chile and the Pacific Ocean.
In 1820 the Army of the North was summoned to intervene in the internal strife between the central government in Buenos Aires and the Federal League provincial caudillo leaders.
Besides the Patricios Regiment and other corps formed during the British invasions, the only troops with some experience were the Blandengues, lancers militia recruited to patrol the borders of the territories still controlled by indigenous people (mapuche and ranquel).
Most of the commanders were civilians or junior officers, put in charge more for their political leanings, status in society or charisma than for their military capacity.
What would later become the Army of the North started with troops drafted by Juan José Castelli by order of the Primera Junta on 14 June 1810, to fight viceroy Santiago de Liniers, who headed a counter-revolutionary movement at Córdoba Province.
With Córdoba occupied on 8 August, they replaced their cabildo and Juan Martín de Pueyrredón was named governor, assuming the post that same month.
Later they continued their march towards Upper Peru, where the Spanish general José de Córdoba y Rojas was commander of the royalist troops.
The battle was not favorable to Balcarce and the outcome undecided, in part for the numerical superiority of the royalist, forcing the expeditionary troops to retreat to the South without pursuit.
The royalist defenses were left in charge of general José Manuel de Goyeneche, who met with Castelli and signed an armistice to last for forty days from 16 May.
General Eustaquio Díaz Vélez with 800 soldiers was sent by Pueyrredón to support the insurrection at Cochabamba in a new attempt to advance on Upper Peru, but were repealed at Nazareno on 12 January 1812.
He was preferred for the post, instead of other more experienced or capable officers as Eustaquio Díaz Vélez or Juan Ramón Balcarce, both colonels at the time and veterans of many battles.
Among the junior officers there were several that would make a name for themselves such as José María Paz, Manuel Dorrego and Gregorio Aráoz de La Madrid.
Belgrano spent the first months of his command in establishing a hospital, military tribunal, supply corps, reconnaissance company and in negotiating the manufacturing of ammunition and clothing.
On 1 July 1812, Belgrano created the 8th Infantry Regiment with men from Upper Peru, but it was disbanded after the defeat at Vilcapugio as most of the officers and more than half their soldiers were lost at the battle.
In Salta he found an intelligence net who was passing information to Goyeneche's royalist army, headed by the city's bishop, whom he forced to leave the territories controlled by the Junta.
The advanced elements consisting of the battalion of mulattoes and the two cavalry regiments of Hussars and Dragoons, reached Humahuaca, while the rest of the army positioned itself in Jujuy.
One of the deserters due to the strict discipline was Venancio Benavídez, who moved to Goyeneche's forces, which had already taken Cochabamba and he told of the harsh conditions at Belgrano's army.
Tristán was forced to retreat north to Salta, lost his artillery and most of his wagons to the independentist army, who needed the supplies and could put them to good use.
The four months he had to reorganize after the victory at Tucumán allowed Belgrano to double the number of men and improve on training and discipline, even though he lost Holmberg, who had made enemies of other officers and was recalled to Buenos Aires.
Warnes and Álvarez de Arenales continued with the resistance in Upper Peru but the first one was killed at El Pari, and the latter obtained victory at La Florida (24 May 1814) and Postrer Valley (4 June), but was later defeated at Sumarpata on 5 August.
The objective this time was to occupy all of Upper Peru, closing the door on the royalists and therefore establishing the sovereignty of the United Provinces of the Río de la Plata.
The Army of the North's officers mutinied and told to Rondeau they would only accept orders from him and disregard Alvear's and they asked him to initiate the campaign.
Continuing forward with the march into Upper Peru, a reconnaissance group found royalist troops encamped at Venta y Media commanded by Olañeta.
Güemes, unhappy with Rondeau, abandoned the army along with his gaucho forces and returned to Salta, carrying with him many of the supplies left in Jujuy.
On 10 December 1816 Belgrano sent La Madrid to quelch the autonomist movement in Santiago del Estero, defeating Juan Francisco Borges's troops at Pitambalá.
On 18 March 1817 a troop of 400 soldiers left San Miguel de Tucumán under the command of general La Madrid to advance to Oruro.
Colonel José Canterac after pacifying Tarija and Cinti, started a new invasion with three columns under command of Olañeta (through Humahuaca), Vigil (through Orán) and Valdez (through Despoblado).
On 27 April they fought at León (12 kilometres (7 mi) north of Yala), where general José Ignacio Gorriti defeated 400 royalists, so Olañeta had to withdraw his forces to Tilcara.
On 22 June Olañeta took Jujuy and advanced to Salta, where finding himself surrounded, he signed an armistice 14 July and returned to Upper Peru.
