The revolution officially began when Castro led a group of rebels in an attack on the Moncada army barracks in Santiago de Cuba. The assault failed, but the political situation was forever changed. Revolutionary sentiment increased throughout the island, yet Castro was in jail for the attack. Once free, Castro fled to Mexico to meet up with fellow revolutionary Che Guevara. Along with 80 other companions, Castro and Guevara returned to Cuba in the ship Granma. After a series of successful battles, the serving president, Batista, fled for his life. This marked the beginning of the Castro regime.