Valdivia left months later to the south with his troops, beginning the War of Arauco. Santiago was left unprotected. The indigenous hosts of Michimalonco used this to their advantage, and attacked the fledgling city. On 11 September 1541, the city was destroyed by the natives, but the 55-strong Spanish Garrison managed to defend the fort. The resistance was led by Inés de Suárez, a mistress to Valdivia. When she realized they were being overrun, she ordered the execution of all native prisoners, and proceeded to put their heads on pikes and also threw a few heads to the natives. In face of this barbaric act, the natives dispersed in terror. The city would be slowly rebuilt, giving prominence to the newly founded Concepción, where the Royal Audiencia of Chile was then founded in 1565. However, the constant danger faced by Concepción, due partly to its proximity to the War of Arauco and also to a succession of devastating earthquakes, would not allow the definitive establishment of the Royal Court in Santiago until 1607. This establishment reaffirmed the city's role as capital.