This notable and long-established surname recorded as Cadigan and Cadogan, and widespread in the Irish provinces of Munster and Leinster, is probably of ancient Welsh origins. It was certainly introduced into Ireland by a follower of Strongbow, the Earl of Pembroke, who invaded the country in 1169, but may have been there earlier. The derivation of the surname is from the pre 7th century personal name "Cadwgan", meaning 'battle-prince', from 'cad', battle, and "mael", prince. The later Earls of Cadogan claim descent from Prince Cadwgan, the ruler of south Wales, who died in the year 1112. Later surname recordings include Major William Cadogan, who was the governor of the town of Trim, Ireland, in 1649, whilst another William Cadogan (1675 - 1726) and born in Dublin, was created the first Earl Cadogan in 1718. The County Cork family of Cadogan are said to be native Irish in origin, but the Gaelic form of their name, "O'Ceadagain", is a version of the Welsh "Cadwgan". In 1341 Thomas and Bartholomew Cadigan, noted in the Gormanston Register of Ireland, were considerable landholders in County Limerick, their 'home' being called by the rather unwieldy name of 'Martyncadyganestown', and probably the modern Martinstown. The first recorded spelling of the family name is shown to be that of Cadivor Cadigan. This was dated 1292, in the "Subsidy Rolls" of the county of Monmouthshire", Wales. Throughout the centuries, surnames in every country have continued to "develop", often leading to astonishing variants of the original spelling.