Pontus was a pre-Olympian sea-god, a son of Gaia and primordial deity. His female counterpart was Thylassa, and upon her he sired fish and other creatures of the sea.
The mosaic image of Pontos on the right, from the Bardo Museum in Tunis, is from theoi.com
Pontus was the name of a Swedish police cadet in Henning Mankell's Wallander series. The actor was handsome, unlike his namesake (at least if the mosaic is anything to go by.
As far as I know, the name Pontus is rarely if ever used in English.