This is a genuine Norman Invasion name introduced at the 1066 Conquest of which at least eleven alternative spellings exist, such as Dol(l)ey, Dul(e)y, Olley and Ollie. It is a French locational name which comes from one of the five villages called Ovillys in Calvados, Normandy, althought the first invaders were from Ovilly Le Basset or Ovilly Le Vicomte. The name development includes: Robert Oilgi also in the Domesday Book, Henri de Olli (1135, Oxford), Henry de Oly (1212, Oxford), Reginald Duly (1297, Yorkshire), John Dolye (1272, Stafford), Robert de Doley (Oxford, 1279) and Robert de Oylly (1378, Oxford). Among the recordings in London is the marriage of Robert D'Oyly and Mary Langley on June 2nd 1745 at St. Paul's, Covent Garden, Westminster, and the christening of Thomas D'Oyly on June 15th 1821 at St. Mary's Lambeth. Probably the most famous name association is of Richard D'Oyly Carte (1844 - 1901), the English impresario noted for his productions of the operettas of Gilbert and Sullivan. The first recorded spelling of the family name is shown to be that of Robert de Oilleio, which was dated 1086, in the Domesday Book, Oxford, during the reign of King William 1, known as "The Conqueror", 1066 - 1086. Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.