Curious about Irish Ancestry

Hello there,

I was born on the Caribbean island of Saint Lucia, and from a young age have been reminded that my mother's father was half Irish and half Indian and settled in Saint Lucia in his early 20s where he met my mother's mother who was mostly African with some Arawak Indian in her ancestry. I belive my grandfather's full name was Ernest Calcahoun Dixon, but unfortunately, that is all I really know about him, as he left my grandmother when he found out she was pregnant with my mother, and was in fact quite the womanizer with girlfriends and children littered around the Caribbean and the USA!

Would anyone have any suggestions on how I might go about doing some research on him, or his parents here in Ireland? Perhaps a registry of births? I can get more clarity on his age at the date of his death and work backwards to determine a general idea of when he was born. How would I go about such a search? I would be grateful for any guidance!

Thank you.

Kind regards,

Chris Lucas