This famous surname is recorded in many forms, including Arcy, d'Arcy, d'Arcey, Darcy, Darcey, Dorcey, Dorcy, Dorsey, D'orsay, Orsay, and Orsi. it is usually of French locational origin, although Irish names may have a different root. The French forms originate from either the village of Arcy in La Manche, named from the Gallic "ars", meaning the bear, and the suffix "-acum", meaning a settlement, or from Orsai village in Seine et Orne. This is a derivative of the Latin personal name "Orcius". The surname was introduced into England in the wake of the Norman Invasion of 1066, when a Norman knight called William de Arecai was granted thirty manors in Lincolnshire by William the Conqueror. Early historical examples of the surname include William Daresci, Roger Arsi, and Thomas Darcy all of Lincolnshire, in the years after 1166.
In Ireland the surname is of dual derivation, being either Norman-French as above, and originally followers of Strongbow, earl of Pembroke, who invaded Ireland in 1169, or as an anglicized form of the native Gaelic "O'Dorchaidhe", meaning a descendant of the dark one. Early historical examples of the name include Michel Duuercy, a witness at the French Huguenot church, Threadneedle Street, London, in 1635, and Richard Dorsey, a witness at the church of Saint Martins in the Field, Westminster, on September 27th 1703. Notable name-bearers include Robert D'Arcy (1718 - 1778), the earl of Holderness, Yorkshire, and Patrick, Count D'Arcy (1725 - 1778), Marshal of France.