 During this time he renewed his friendship with <unk> López and the other Cuban exiles whom he had met in Guatemala . In June 1955 , López introduced him to Raúl Castro who subsequently introduced him to his older brother , Fidel Castro , the revolutionary leader who had formed the 26th of July Movement and was now plotting to overthrow the dictatorship of Fulgencio Batista . During a long conversation with Fidel on the night of their first meeting , Guevara concluded that the Cuban 's cause was the one for which he had been searching and before daybreak he had signed up as a member of the July 26 Movement . Despite their " contrasting personalities " , from this point on Che and Fidel began to foster what dual biographer Simon Reid @-@ Henry deems a " revolutionary friendship that would change the world " , as a result of their coinciding commitment to anti @-@ imperialism . 
