Under Pedro de Valdivia's wing, Lautaro quickly learned horse-riding and Spanish military techniques that he would use later in the war that was taking place at the moment.

At the same time, Pedro de Valdivia was using a policy of quickly founding cities, and dispersing his forces in the conquered territory.

Meanwhile, the Mapuche leader Lautaro kept the forces of Gómez de Almagro bottled up in the nearby fort of Purén through various trickery.

The tranquility and the occasional sightings of Indians in the distance continued to raise his suspicion, and he sent an advance scouting team of five men under the command of Luis de Bobadilla to explore the road ahead and return information about the location of the enemy.

In December 1553, Mapuche forces, under the command of the vice toqui Lautaro attacked and destroyed the fort using the battle tactics learned from the Spanish.

A second squadron of Mapuches attacked, this time armed with maces and ropes as well as lances, with which they succeeded in dismounting the unfortunate Spanish caballeros, whom they quickly dragged out of the battlefield once they were on the ground.

Valdivia, aware of the desperate situation due to the Spanish losses and fatigue, gathered together his available men and threw himself into the bitter fight.

According to Jerónimo de Vivar, the toqui Caupolicán personally ordered the execution of Valdivia, who was killed with a lance and his head, along with those of the two other bravest Spaniards, were put on display.

[4] Alonso de Góngora Marmolejo writes Valdivia offered as a ransom for his life that he would evacuate the Spanish settlements in their lands and give them large herds of animals, but this was rejected and the Mapuche cut off his forearms, roasted and ate them in front of him before killing him and the priest.

[citation needed] Following the battle Caupolicán went on to blockade the city of Valdivia and the few remaining Spanish settlements in the south of Chile.