COSTELLOE Family History

Recorded in the spellings of Costello (County Mayo), Costelloe (Counties Galway and Clare), and sometimes Costley, Cusheley, and Casserly, this famous surname is Irish, but of Norman-French origins. It derives from the pre 10th century family known as the 'de Anglos' or Nangle, which strictly speaking means 'from or of, England'. It is claimed that the first reference to the clan in surviving registers or charters is that of Gilbert de Nangle in in the book known as 'The four masters' and dated 1193.