This is a dialectal variant of Chadwick from any of the places so called, for example Chadwick in Lancashire, Warwickshire and Worcestershire. The name derives from the Olde English pre 7th Century personal name Ceadda (Ceadda was the name of an Anglo-Saxon bishop, later St. Chad), plus the Olde English "wic", a dairy farm or settlement. The surname is first recorded in the early half of the 13th Century, (see below). In 1328, one, Andrew de Chadewyke appears in the 1328 "Chartulary of Whalley Abbey". Variations in the idiom of the spelling include Chaddock, Shadwick, Shaddick, Shaddock, Shattock, Shadrack, Shedrik, Shadrak, Chaddrick, etc.. One John, son of Henry and Anne Shedrak, was christened on March 29th 1657 at St. Dunstan, Stepney, and William Shadrack married Jane Alid on March 11th 1798 at St. Matthew, Bethnal Green, London. The first recorded spelling of the family name is shown to be that of Richard de (of) Chadelswic, witness. which was dated 1221, The Assize Court Rolls of Warwickshire. during the reign of King Henry 111, The Frenchman, 1216 - 1272. 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.