He was the eldest son of Waltheof, Earl of Dunbar and Alina, and succeeded to his father's titles upon the latter's death in 1182.
Patrick was one of the most important magnates to Kings William and Alexander II of Scotland, frequently witnessing their charters and traveling in their entourages whenever they went to the south of England to perform homage to the King of England for the properties in that realm.
Like his predecessors (who were originally of the kindred of the native English earls of Northumberland), some of Patrick's most important lands were in northern England.
Patrick's close association with the Scottish kings in fact got him in trouble, and perhaps because of Alexander II's pursuit of claims to the earldom of Northumberland, Waltheof found himself temporarily deprived of some of his lands by King John of England.
Patrick married (1) Ada (died 1200), an illegitimate daughter of King William the Lion, by whom he had four sons and a daughter: His first wife predeceasing him, Patrick married again: (2) Christina, widow of William de Brus, 3rd Lord of Annandale.