The Isle of Man has always been independent of England and it does not form part of the United Kingdom. It issues its own coins, as do Jersey and Guernsey in the Channel Islands.
Taken straight from the Royal Mint FAQ:
"The Channel Islands and the Isle of Man are Crown Dependencies of the United Kingdom. They have their own legislative and taxation systems and issue their...
The Ellan Vannin coins were issued from 1988 to 1995, more or less. These coins are still potentially in circulation so, unless they are part of a Proof or Uncirculated mint set or are individual...
The 1975 Isle of Man 'MANX CAT' CROWN (25p) would be worth around £2 - £3 (September 2010). They often come in plastic cases surrounded by a red cardboard for presentation. The same coin was also...