The de Tosny family were prominent in Normandy in the Middle Ages.
The following article gives a good background.
Normandy then and Now
Raoul de Tosny was my 32 x great grandfather, his son, Robert my 31 x great grandfather, and his daughter Adeliza de Tosny my 30 x great grandmother. She married Roger Bigod, and their daughter Maud is my 29x great grandmother.
Later, my 26x great grandmother Ida de Tosney (who married a different Roger Bigod) was the mother of Henry II's illigitimate son, my 25x great grandfather William Longspee, 3rd Earl of Salisbury.
