This is an example of an English locational surname and comes from the town of Haydock in Lancashire. The placename is first recorded in 1169 (in the Lancashire Pipe Rolls) as 'Hedoc' and derives from a Welsh name 'Heiddiog' meaning 'barley place' or 'corn farm' from the Welsh 'haidd', barley. In the modern idiom the surname is also found as 'Haddock', which is the local pronunciation of the placename. Locational names were used especially for those people who left their original homes and went to live or work in another town or village. One William Haydock (d. 1537) a Cistercian monk, was executed for participating in the Pilgrimage of Grace. His body was found at Lottam Hall in the early 1800's. The first recorded spelling of the family name is shown to be that of Hugo de Haidoc (witness). which was dated 1212 The Fees Court Records of Lancashire. during the reign of John 'Lackland' 1199-1216. 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.