 The son of Colonel John Joseph O'Sullevan , resident magistrate at Killarney, and Vera (), Peter O'Sullevan was born in Newcastle, County Down before returning as an infant to his parents' home at Kenmare, County Kerry but brought up in Surrey, England.He was educated at Hawtreys, Charterhouse, and later at Collège Alpin International Beau Soleil in Switzerland.O'Sullevan was involved in some of the earliest television commentaries on any sport in the late 1940s and made many radio commentaries in his earlier years (including the Grand National before it was televised for the first time in 1960).