When he was 15 years old, he joined the Liberation Army of the South under the direct command of Emiliano Zapata.
[2] During the 1920s and 1930s, Jaramillo advocated on behalf of ejidos, grants of communally owned land by the federal government to farmers.
He supported the 1934 presidential campaign of Lázaro Cárdenas, who created a cooperative sugar mill in Zacatepec in 1938 at Jaramillo's urging.
[3] In 1944, President Manuel Ávila Camacho invited Jaramillo to Mexico City to negotiate an end to the fighting.
He founded the Agrarian Labor Party of Morelos (Partido Agrario Obrero Morelense, or PAOM), which quickly had 15,000 members.
The government asked Jaramillo to help remove the squatters while the legal process continued; most of the farmers agreed.
When the federal government ultimately turned down the farmers' request for assistance, Jaramillo appealed to López Mateos but the president refused to meet with him.
[13] A few days after the murders, Carlos Fuentes went to Xochicalco and wrote an article that was published in Siempre!, a popular magazine:[14] They pushed him down.
He threw himself at the party of murderers; he was defending his wife and his stepchildren, they brought him down with their rifle butts, they knocked out an eye.
After that it went fast; [the other sons] fell riddled with bullets; the submachine guns spat on the five fallen bodies.