Answer: Columbus (to the Caribean, late 15th century), Cabot (North America, New Foundland), Vasco da Gama (early 16th century, along to the coast to west Africa to the southern hemispere and Cape of the Good Hope), Pizzaro was "conquistador" who explored and conquered Peru (Inka empire, western part of the South America).
Explanation: Columbus was Italian in the service of Spanish crown, Cabot was Italian as well in the service of English crown, Vasco da Gama was Portuguese in the service of Portuguese crown, Pizzaro was Spaniard in the service of Spanish crown.
