The Irishman Bernard Phelan acquired the Domaine Le Clos de Garamey in 1805 and Ségur de Cabarnac in 1810. In Ireland, he was a neighbour and friend of Hugh Barton who established Château Léoville-Barton. By his death in 1841 the estate combined to form Château Ségur de Garamey, which passed on to his son Frank Phelan, 30 years a mayor of Saint-Estèphe. The property was sold in July 1919 to Joseph Chayoux, President of Champagne Chamber of Commerce, whom further developed the brand until before the first world war when the property was sold. It was bought by Xavier Gardinier in 1985 and is now run by his sons, Thierry and Laurent.
Phélan-Ségur's 66 hectares of vineyards are well-sited near the Grionde estuary and lies on well drained gravel soils.
Frank Phelan is the second wine of Chateau Phelan Segur. It was first made in 1986. It bears the name of estate founder Phélan’s son. Frank Phélan was a man of character, mayor of Saint Estèphe for 30 years.