Recorded as Sidney and Sydney, this is an English personal name and enobled surname, although one of early French origins. It derives from the Latin spelling of "de Sancto Dioniso" (St Denis) and used in early French recordings. Like other English surnames such as Semple from St Paul, Sinclair from St Clare, or Sinjon from St John, it is a good example of the medieval English "fusings" which either intentionally or otherwise, disguised the true origin of a name. The famous Victorian etymologist Canon Charles Bardsley writing in the year 1880 claimed that the first name holder was Sir William de Sancto Deonise, chamberlain to King Henry 11nd (1154 - 1189), and surviving charters seem to indicate that this was so. Indeed this was the spelling for several centuries and it only seems to have changed to more or less the modern form around the time of the beginings of the reformation in the 15th century. The surname became prominent because of Elizabethan gentlemen such as Sir Phillip Sidney M.P., playright, politician, poet, soldier (1554 - 1586), who died a heroic and young death whilst trying to drive the Spanish out of Holland. He was followed by other name holders such as Algernon Sydney also spelt Sidney, (1622 - 1683), earl of Leicester, and Henry Sidney, earl of Romsey, who in 1688 was a close supporter of William of Orange.