Answer : 1. "336 BC"
Explanation :

Alexander the Great became the king of Macedonia in 336 BC after the assassination of his father, King Philip II of Macedon. Following his accession to the throne, Alexander went on to become one of history's most successful military commanders, leading his armies to conquer vast territories and create one of the largest empires in the ancient world. His reign had a significant impact on the course of history and left a lasting legacy.