Answer:
His surname is Castro, his full name is Fidel Alejandro Castro Ruiz, or Fidel Castro.
He was a Cuban lawyer, revolutionary, political leader, and according to some (depending on your political orientation) dictator who ruled Cuba for half a century.
He led the small group of guerrillas that took power from Fulgencio Batista in 1959, and two years after, established in Cuba a communist-inspired goverment aided by the Soviet Union.