What society first discovered that different places on earth are at different times of day? For example did the ancient Greeks know that the sun set at different times at either end of Alexander's Empire.

by that-T-shirtguy
jschooltiger

This was understood in classical antiquity: https://www.reddit.com/r/AskHistorians/comments/3uufv2/when_did_people_understood_the_concept_of_time/