This interesting and unusual English surname, found widespread in the county of Suffolk, derives from the old Norse personal name "Kupsi" or the old Swedish "kofse", of uncertain origin, but recorded in the Domesday Book of 1086 as "Copsi" and apparently was used as a fairly frequent given name in the early Middle Ages. The surname itself first appears in records in the late 12th Century (see below). Copi or Copsige (deceased 1067), Earl of Northumberland under Tostig in 1065 submitted to William the Conqueror in 1066 and was created Earl and sent to reduce Northumberland, and was later slain by Oswulf. Robert Copsi was recorded in 1182 in the Pipe Rolls of Staffordshire. Jone, daughter of John Copsey was christened at Barrow in Suffolk on July 1st 1543, while at Glemsford, Suffolk Thomas, son of Richard Copsey was christened on February 7th 1551. Gilbert Copseye was christened at the Church of St. Mary the Virgin, Dover, Kent on March 6th 1574. The first recorded spelling of the family name is shown to be that of Hugo Copsi, which was dated 1170, The Pipe Rolls of Warwickshire, during the reign of King Henry 11, "The Builder of Churches", 1154 - 1189. 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.