of La Frontera (The Frontier), the boundary between Spanish territory and the land of the Mapuche, an American Indian ethnic group that remained independent until the 1870s. The settlement was formally recognized by the Spanish authorities as a town two years later by a royal decree. It was given a coat-of-arms that is still in use today. At the time of the Spanish arrival to the Concepción area chronicler Jerónimo de Vivar noted local Mapuches wore gold and silver bracelets and "sort of crowns". This is interpreted either as Incan gifts, war spoils from defeated Incas, or the adoption of Incan metallurgy. Although Concepción was a significant military settlement for the Captaincy General of Chile, it was overrun and destroyed by Mapuche armies in 1554, and once again after being refounded in 1555. Concepción was restored during the governorship of García Hurtado de Mendoza when he landed there and built a fort on the Alto de Pinto in 1557. The town was refounded once more on January 6, 1558, by captain Jerónimo de Villegas. It became the headquarters of the military forces engaged against the Mapuche in La Araucanía over the next two centuries, growing to a population of 10,000 despite a siege in 1564 and other attacks by the Mapuche. Concepción was the home of the Real Audiencia from 1565 to 1575. Earthquakes and tsunamis, which razed the town in 1570, 1657, 1687, 1730 and 1751, led the authorities to move the town to its current site in the Valle de la Mocha, alongside the Bío Bío River; the old site lay empty until March 29, 1842, when the present town of Penco was founded. The new site for the town of Concepción became the main town of the Intendancy of Concepción, whose jurisdiction extended from the Maule River to La Frontera. The first Intendant of Concepción was the Irishman Ambrose O'Higgins, Marquis of Osorno, who later became Royal Governor of Chile and Viceroy of Peru. When the First National Government Board met in Santiago on September 18, 1810, citizens of Concepción joined up. Concepción was used as the point of entry by the Spanish Army in the attempt by the Viceroyalty of Peru to re-conquer Chile. Concepción politicians and soldiers became a significant political force in the newly independent country. On January 1, 1818, Ambrose O'Higgins's son, Bernardo O'Higgins, proclaimed and took the oath of the Chilean War