 Between 1549 and 1553, after his arrival back in Santiago, Valdivia again undertook the conquest of southern Chile, but faced heavy resistance from the indigenous population.Valdivia had a clash with the warlike Araucanians beyond the Bio-Bio River in 1550 in which he defeated them but by no means broke their will to resist, a will that grew stronger when the conquistador established settlements in their territory.In spite of the fierce resistance at the Battle of Penco, he founded Concepción in 1550.