Tar-Súrion was the grandson of Tar-Ancalimë, Númenor's first Ruling Queen. His father Tar-Anárion had two daughters who were both older than Tar-Súrion, and thus had a claim on the throne. Both of these refused the rule of Númenor, however, and so Tar-Súrion received his father's Kingship.
We know little of Tar-Súrion's reign, except that he ruled at a time when the Elves of Eregion had begun the forging of the Rings of Power. His eldest child was a daughter, and when he gave up the Sceptre she became the second Ruling Queen, Tar-Telperiën.