I believe that Velasco was a representative of the left wing of the Peruvian Armed Forces at the time. He took office in a bloodless coup d'état because Peru was suffering from political instability, the Congress was under the control of the extreme right. The executive was under the control of a weak and useless liberal, in addition to the existence of communist and socdem guerrillas (APRA Party).

The army decided that enough was enough and, fearing that there would be a far-right party in coalition with the APRA government in Peru, which would lead to greater political instability, they staged a coup d'état and ousted the President. During his rule, he was pro-Inca and pro-Native, granting a series of rights and changing the names of things to indigenous names. He also established Quechua as one of Peru's official languages. This process was called Peruanism. He also carried out the largest land reform in South America (second only to Cuba in Latin America). He nationalized the economy, the government took over many things.

He began to have better relations with Cuba, even though his government was anti-communist and persecuted socialists, liberals, conservatives and communists. He started buying things from the Soviet Union and Cuba to prepare for a possible invasion of Pinochet's Chile. He also didn't like the US and tried to gain a lot more independence from the US. What really screwed Velasco up was the oil crisis of the 1970s, which made it impossible for Velasco to continue his revolution and eventually opened up the opportunity for the right-wing members of the army to depose him.

Btw, Bolivia also had their very own Center-Left Military strongman (1969 - 1971), Gen. Juan José Torres (nicknamed Jota-Jota) who kicked the Americans out of Bolivia, and later he was removed and killed by the CIA.