This interesting surname is of early medieval English origin, and is locational from a now "lost" place, thought to have been in Berkshire, due to the large number of recordings in this county. The surname is derived from the Middle English (1200 - 1500) personal name "Sad", from a nickname for a serious or solemn person, itself derived from the Middle English "sad", serious, grave, from the Olde English pre 7th Century "soed", weary, tired, and the Olde English "graf", grove, thicket, and means "Sad's grove". An estimated seven to ten thousand villages and hamlets are known to have disappeared in Britain since circa 1100, due to such natural disasters as the Black Death of 1348, in which an eighth of the population perished, or to the widespread practice of "clearing" large acres of land to make sheep pastures during the height of the wool trade in the 14th and 15th Centuries. Among the recordings in Berkshire are the marriage of Henry Sadgrove and Johannah Forster on October 20th 1692 at St. Mary's, Reading, and the christening of Edward, son of Edward and Ann Sadgrove, on January 21st 1753 at Basildon. The first recorded spelling of the family name is shown to be that of Margerye Sadgrove, which was dated March 26th 1600, marriage to Thomas Ruffyman, at South Moreton, Berkshire, 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.