Mr. A. W. Moore of Cronkbourne, near Douglas, Speaker of the House of Keys and a noted Manx historian, wrote in his “Manx Names”, published in 1906, that the origin of the Cain(e) surname is contracted from Mac Cathain, “Cathan’s Son”.  This name may be rendered “warrior” (cath, a battle”).   Various versions of the name, as found on the Isle of Man are McKane in 1408, McCann in 1430, MacCane in 1511, Cain in 1586, Cane in 1601, Caine in 1609 and Cayne in 1610.   The surname is well documented and researched within the Isle of Man.  Had it not been for the Manx custom of dropping the prefix “Mac” from surnames the present form of the name would have been McCain.  This practice appears to have begun in the 1500’s as in the example of Cain in 1586.  Many Manx surnames beginning with “C”, “K”, or “Q” were originally “Mac” names.