The Communist leader also sought to buy weapons from arms dealers connected with Germany's extreme Right, showing the extent to which he was prepared to collaborate with his ideological enemies to prevent a US invasion on the Caribbean isle.
Papers released this week by the Bundesnachrichtendienst (BND) - the German foreign intelligence agency - show information gathered by German operatives 50 years ago during the tense days of the Cuban missile crisis.
They reveal that Castro personally approved a plan to hire former Nazi officers to instruct the Cuban revolutionary army, offering them wages that were four times the average salary in Germany at the time and the chance to start a new life in Havana.
They papers, dating from October 1962, show that four former officers from the elite Nazi death squads had been invited to the Cuban capital, although subsequent reports could only confirm that two had arrived.
It also showed how the Castro regime negotiated with two traffickers linked with Germany's far Right to purchase Belgian made pistols to arm the Cuban forces.