The Argentine Army (Spanish: Ejército Argentino, EA) is the land force branch of the Armed Forces of the Argentine Republic and the senior military service of Argentina. The Army's official foundation date is May 29, 1810 (celebrated in Argentina as the Army Day), four days after the Spanish colonial administration in Buenos Aires was overthrown. The new national army was formed out of several pre-existing colonial militia units and locally manned regiments; most notably the Infantry Regiment "Patricios", which to this date is still an active unit. It was only with the establishment of a constitution (which explicitly forbade the provinces from maintaining military forces of their own) and a national government recognized by all the provinces that the Army became a single force, absorbing the older provincial militias. The Army went on to fight the War of the Triple Alliance in the 1860s together with Brazil and Uruguay against Paraguay. After that war, the Army became involved in Argentina's Conquista del Desierto ("Conquest of the Desert"): the campaign to occupy Patagonia and root out the natives, who conducted looting raids throughout the country. After 1880, the Army sought to become a professional force without active involvement in politics, even though many a political figure -President Julio Argentino Roca, for example- benefitted from a past military career. The Army prevented the fall of the government in a number of Radical-led uprisings. Meanwhile, the military in 

general and the Army, in particular, contributed to develop Argentina's unsettled southern frontier and its nascent industrial complex. The main foreign influence during this period was, by and large, the Prussian (and then German) doctrine. Partly because of that, during both World Wars most of the officers supported the Germans, more or less openly, while the Argentine Navy favored the British instead. The 1st Infantry Regiment "Los Patricios" (Regimiento de Infantería 1 "Los Patricios") is the oldest and one of the most prestigious regiments of the Argentine Army. The title is often shortened to the Patricians' Regiment (Regimiento de Patricios). The regiment was formed as the Legión Patricia ("Patricians' Legion) from inhabitants of Buenos Aires in 1806 to fight against the British invasions of the River Plate. Among some of its first members, it included a woman, the Alférez (approximately, second lieutenant) Manuela Pedraza, one of the heroes of the Defense of Buenos Aires in 1806. The regiment, therefore, existed prior to Argentine independence. Their first commander was Cornelio Saavedra. The regiment also fought in May Revolution, Cisplatine War, Platine War, Paraguayan War, Dirty War, and Falklands War. Although the word "Patrician" is usually employed as a synonym for aristocrat, in the naming of the Regiment it meant "the sons of the homeland" (Spanish "Patria" meaning "homeland"). Indeed, the original members of the Regiment were not aristocrats but Criollos, who were much farther down in the social hierarchy of the time. Prior to the arrival of British troops, Viceroy Santiago de Liniers decided that volunteers are drawn from the population of Buenos Aires muster at the Fort on 15 September 1806. More than 4,000 men appeared, who had to be enrolled in other military units. It was the largest and most powerful unit recruited for the Defense of Buenos Aires and, like other urban military units formed, was granted the privilege of electing its officers. The first election was held at the Consulate of Buenos Aires on November 8, 1806. Lieutenant Colonel Cornelio Saavedra was elected as head of the Corps or Legion and commander of the 1st Battalion, Esteban Romero was elected commander of the Second Battalion, and José Domingo Urien the Third Battalion commander. Manuel Belgrano was elected Sergeant Major (later replaced by Juan José Viamonte) and among other officers commissioned were Feliciano Chiclana, Vicente López y Planes, and Eustace Perdriel Gregorio Díaz Vélez. St. Martin of Tours became the patron of the unit and on 9 November the regimental colors were consecrated with full ceremonial at the Cathedral of Buenos Aires along with that of the Arribeños Corps. The unit was then called the Buenos Aires Patrician Volunteer Urban Legion, with the status of a full Tercio or Colonial Regiment of Militia. During the second British invasion of the River Plate, Saavedra was deployed to Colonia del Sacramento with a contingent of troops, but after the British captured Montevideo he returned to Buenos Aires in February 1807. On 7 June 1807, during the battle of San Pedro in the Banda Oriental, the Spanish forces from Buenos Aires led by Francisco Javier Elio, including several companies of the Patricians Legion, were preparing to storm Colonia del Sacramento. The British, under Lt. Col. Denis Pack, attacked and defeated them. The whole unit had its baptism of fire on 4 July 1807 when the British attacked Buenos Aires. The 1st and 2nd Battalions of the Patricios Legion were located in the Division of Right (red flag), while the 3rd Battalion was in the Reserve Division (Tricolor). The Legion, together with the other urban military battalions deployed, won that battle. Shortly after its successful baptism of fire of 1807, Saavedra and the patricians made an important new service to the public. On January 1, 1809, the Cabildo of Buenos Aires, with support from the Spanish military units, tried to replace the viceroy Liniers with a Government Junta headed by Martin de Álzaga and create the "American Spain", before the occupation of Europe by the advancing Napoleonic armies. This was known as the Mutiny of Álzaga. Cornelio Saavedra, with the legion under his command and the native personnel from the other battalions of militias managed to abort the move and ensure the authority of the viceroy, obtaining as a result of these developments the dissolution of the Spanish rebel units prompting the viceroy to reinstate full control over the military. It also cleared the way for the natives who sought independence. On January 13 the same year, as the Legion began to recover, it became the Patricians Corps by Royal orders via the Junta of Seville, and several of its officers received royal promotions. The Chuquisaca Revolution in May and the La Paz revolution in July saw the second combat action of the Patricians. Led by captain Diego Basavilbaso, two companies of the Patricians Corps joined the pacification forces of Vicente Nieto and Colonel Jose de Cordoba in Upper Peru that October, ending the revolutions on October 31 that year with Chuquisaca (today's Sucre in Bolivia) reoccupied by the royalist forces. The May Revolution's main protagonists, Saavedra and the Patricians Corps would be successful during the days leading up to May 25, 1810, open cabildo of Buenos Aires, which resulted to the Viceroy's forced resignation and the birth of the Primera Junta. This is the reason why the Patricians Regiment is often called The Sword of May. 4 days after its formation, the new Primera Junta, led by Saavedra as its President, formally announced, through a May 29, 1810 proclamation, that the Buenos Aires Militia Battalions of Infantry are now the very first line infantry regiments, with the other service and arms regiments soon to be raised. As a result, the Argentine Army was born, with the first units being that of the Patricians' Legion, by now the "Patricians" 1st and 2nd Infantry Regiments coming from the 1st and 2nd Battalions, Patricians Corps. The order of June 8, 1810 (also by the First Junta) formally permitted racial integration into the new force of the mulattooes (blacks, pardos and natives) of the Castas Militia Battalion. They were to serve with a new regiment (the 3rd Inf. Regiment), while some servicemen from this battalion were to serve as part of the 2nd Infantry Regiment. On behalf of the First Junta and later of the Junta Grande, the Patricians Regiments went to the former viceregal provinces to formally ask for their inclusion into the new First Junta (and later the Great Junta) and to send their delegates, as well as for the liberation for the former viceregal towns and cities. By June 8, they were part of the newly formed Army of the North commanded by Colonel Francisco Ortiz de Ocampo and Lieutenant Colonel Antonio Gonzales Balcarces as part of the Upper Peru campaign. The first companies of both regiments were included, and by November 3, these companies joined the newly formed 6th Infantry Regiment together with troops and officers from Tucuman and Santiago del Estero. The two companies represented the Patrician Regiments during the Army of the North's first battles. By September, the 1st Coy., 1st Infantry Regt. and 1st Coy., 2nd Infantry Regt. joined and participated in the Paraguay campaign on behalf of their regiments. March the next year saw representatives of the 1st and 2nd Infantry join the Liberation of Uruguay campaign as part of the Vanguard Division. Saavedra soon resigned as unit commander of the 1st Regiment on November 11, 1811 and was replaced by Manuel Belgrano. At the same day, the 1st and 2nd Infantry Regiments merged to become the 1st Infantry Regiment "Patricios" with Belgrano as the commander of the new regiment. On December 6, 1811 a mutiny led by a squad of the Patricians Regiment mutinied against their new commander, for the preservation of the regiment's privileges, now removed by the First Triumvirate. It ended in failure, and the mutinied squad was executed on December 11 the same year, on Bernardino Rivadavia's orders. The merger, as well as other reasons, caused many problems for the new 1st Infantry Regiment. Despite it all, it participated in all other military actions on behalf of the First Triumvirate. Examples of such battles were the Battle of Tucuman, the Battle of Salta, the battles at Vilcapugio, Ayohuma, and the Battle of Sipe-Sipe, all led by their commander, Col. Belgrano. In 1812, he even presided over the creation of the Flag of Argentina in the presence of the Patricians Regiment of Foot in Rosario on February 20. Afterwards, it was placed in active service in Buenos Aires months after its Uruguayan deployment. The regiment fought in the Argentina-Brazil War in 1827 and was disbanded in its aftermath, being replaced by the militia battalions of Buenos Aires, in a time of great troubles due to nationwide civil war. It was only in 1830 when Juan Manuel de Rosas honored the service of these battalions with the Patricians honorific, and the regiment was reinstated, just in time for Rosas's Desert Campaign in 1833, and moved on to Martin Garcia island in 1838. In 1846, the regiment was part of the Argentine land forces that fought in the historic Battle of Vuelta de Obligado.