He was known as the leader of the first Ilocano revolt against the Spaniards. He was the rich leader of San Nicolas. Along with the leader of Bangui, Juan Magsanop, they planned secretly to free Ilocos from the Spaniards. When the Pangasinense revolt led by Andres Malong in 1660 and the Spaniard troops left Ilocos to fought the revolt in Pangasinan they find the best time to . They contacted another leader, Gaspar Cristobal, the chief of Laoag. Cristobal burned the church of Laoag as a sign of his support. They also sought the help of the Kalingas also to kill the Spaniards.
The Ilocanos and the Kalingas crowned Pedro Almazan with a stolen crown of a statue from the burned church. They proclaimed "Long live Manong Almazan, the King of Ilocos". The people waved banners in the street.
The revolt reached the towns of Cabicungan (now Claveria) and Pata (now Claveria) in Cagayan.
On February 1661, the revolt was known by the Spaniards in southern part of Ilocos who were then celebrating the victory over the Zambals and Pangasinenses. They sent a large troop led by Lorenzo Arqueros along with some natives of Cagayan and Southern Ilocos and attacked Almazan's troops. They were taken in sudden so Almazan retreated his troop to the forest. The Spaniards followed them with the help of the natives. Juan Magsanop's group were the first to be captured. Before the Spaniards captured Magsanop, he killed himself with a knife.
When Almazan's group was surrounded next. Filled with rage, Almazan attacked the enemy and died while fighting.
With the two leaders dead the rest of the troop escaped and the revolt ended.
Pedro Almazan - an Ilocano pride. His love of his native land that lead him fighting the enemies until his last breath is a good picture of patriotism.