Amid Napoleon's occupation of Spain and the collapse of royal authority, Santiago's cabildo formed a governing junta loyal in name to the deposed King Ferdinand VII but effectively autonomous. The date, later celebrated as Chile's Fiestas Patrias, did not bring immediate independence — that took until 1818 and years of war — but it opened the era of criollo self-rule that ended three centuries of Spanish colonial administration.
News that Napoleon's brother sat on the Spanish throne traveled slowly across the Atlantic, but its effects were seismic. In Santiago, elite criollo landowners used the crisis of legitimacy to convene an open town council, the cabildo abierto, and install a junta that claimed to govern only in trust for the exiled Ferdinand VII. It was a careful legal fiction: nobody yet dared call it a break from Spain.
The junta's president, the elderly Mateo de Toro y Zambrano, presided over a body dominated by younger reformers eager for trade liberalization and greater local control. Within a year the movement radicalized under leaders like José Miguel Carrera, and by 1814 Spanish royalists had crushed the rebellion at the Battle of Rancagua, forcing independence leaders into exile in Argentina.
It took Bernardo O'Higgins and José de San Martín's Army of the Andes, crossing the mountains in 1817, to secure what the junta had only gestured toward. Chile formally declared independence on February 12, 1818. Yet Chileans mark September 18 — not that later date — as their true national holiday, celebrating the moment self-government first became thinkable rather than the moment it was finally won.
Key people: Mateo de Toro y Zambrano, Bernardo O'Higgins