Who was Catweastle?

Catweazle is a fictional wizard created by British author Richard Carpenter between 1965 and 1970 for radio and later appearing in children's books and the 1970–1971 TV series of the same name, starring Geoffrey Bayldon. In the stories, Catweazle finds himself displaced into modern 20th century England through time-travel from 11th century England or Wales at different periods.