Question

Belgrade and hungary became part of the ottoman empire during the reign of which leader? Constantine XI Mehmet II Suleyman I Osman I

Answer 1

It was Suleyman I, also called Suleyman the Magnificent.

He captured Belgrade in 1521. He even laid a siege to Vienna in 1529, but he didn't win. Still - Vienna is pretty far, and this means all the areas UNTIL Vienna were taken by him- a huge portion of Europe!