It seems that Junior's dad, Hil'dyard, was born on the island of Montserrat before moving to Jamaica, where he met Junior's mum. Later on he moved to England, where Junior was born. Don't think there are many footballers out there who qualify for England, Montserrat and Jamaica!
Mendes has never set foot on the island of Montserrat, but will be there when he plays against St Kitts & Nevis, Antigua and St Lucia in a few weeks time. Going by the rankings on the FIFA site, Montserrat are the worst country in the world, so even a Scotland side with Berti Vogts in charge would probably beat them.
Junior was part of the Saints team that won the title in 2000 before moving to Dunfermline, much to everyone at Love Street's anger. he returned for a few months in 2002, before going to Mansfield in January 2003, and moving to Huddersfield 18 months later, where he now is.
You can read a bit more about Junior's call ups on the Huddersfield website, and there are also articles on icHuddersfield here and here.