Gilbert de Moravia, later Saint Gilbert, founded the cathedral in 1224 as the seat of the diocese of Caithness. In 1570 the Mackays of Strathnaver burned it during a local feud, and it stayed partly ruined for more than 250 years. The Countess of Sutherland paid for a restoration in 1835–37. William Burn's work replaced the ruined aisled medieval nave with a narrower new one.
It's a Church of Scotland parish church today, so "cathedral" is a courtesy title. The building is warm red-gold sandstone set in an old graveyard on the green, with the former bishop's palace next door.