Nearchus or Nearchos was one of the Greek officers, a navarch, in the army of Alexander the Great. He is known for his celebrated expeditionary voyage starting from the Indus River, through the Persian Gulf and ending at the mouth of the Tigris River following the Indian campaign of Alexander the Great, in 326–324 BC.

Alexander III of Macedon, most commonly known as Alexander the Great, was a king of the ancient Greek kingdom of Macedon. He succeeded his father Philip II to the throne in 336 BC at the age of 20 and spent most of his ruling years conducting a lengthy military campaign throughout Western Asia, Central Asia, parts of South Asia, and Egypt. By the age of 30, he had created one of the largest empires in history, stretching from Greece to northwestern India. He was undefeated in battle and is widely considered to be one of history's greatest and most successful military commanders.