This unusual surname, recorded in English Church Registers from the mid 16th Century, under the variant spellings Sadry, Sidry, Sidary, Sidery, Sydry and Sodory, is believed to be of topographical origin from residence on or by an extensive patch of hill pasture. The derivation is from the Olde English pre 7th Century "sid", broad, spacious, with the Old Norse "erg", a shieling, hill pasture. Topographical surnames were among the earliest created, since both natural and man-made features in the landscape provided easily recognisable distinguishing names in the small communities of the Middle Ages. On October 3rd 1616, Jane Sydry and Thomas White were married at St. Aldwyn, Coln, Gloucestershire; and on February 22nd 1679, the marriage of John Sadory to Judy Aldredge took place at Bratton, Wiltshire. On April 10th 1720, Joseph, son of John and Mary Sidery, was christened at Upton, Berkshire, and on May 7th 1809, Elizabeth Sidery married a John Whiteburn at St. Martin in the Fields, Westminster, London. The first recorded spelling of the family name is shown to be that of Olyver Sadry, which was dated July 25th 1568, marriage to Johane Francis, at South Weald, Essex, during the reign of Queen Elizabeth 1, known as "Good Queen Bess", 1558 - 1603. 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.