 The King Charles Spaniel and the other types of toy spaniels were crossbred with the Pug in the early 19th century to reduce the size of the nose , as was the style of the day . The 20th century saw attempts to restore lines of King Charles Spaniels to the breed of Charles II 's time . These included the unsuccessful Toy Trawler Spaniel and the now popular Cavalier King Charles Spaniel . The Cavalier is slightly larger , with a flat head and a longer nose , while the King Charles is smaller , with a domed head and a flat face . 
