Trat Province, of which Koh Chang is a part, has a recorded history dating back to the Ayutthaya era ( 1350-1767 ), when it was known as Baan Bang Pra. It was during the reign of perhaps the most famous king of that era, Naresuan ( 1555-1605 ), that Koh Chang gained its name. Approached by boat, the island was thought to resemble an elephant, so Koh meaning island and Chang , elephant, was duly coined.