Originally Posted by Northern_Autumn
My grandmother was British but she emigrated to Canada at some point and married a Canadian. She had 2 children in Canada, one of whom went on to become my father....only it was the freewheeling 70's and my parents didn't get married. As a matter of fact a name is not even written in as my father on the birth certificate....
Could I use a combo of birth certificates/marriage licensce and DNA tests to prove that I was related to him and he was the child of a UK subject?
The main rules relating to leave to enter/remain on the grounds of ancestry are
paragraphs 186-193 of the Immigration Rules. You also need to have a look at
paragraph 6 (interpretation).
If you are serious about doing this, then you will need to have an entry clearance (basically, a visa) before you go to the UK (see the requirement at paragraph 186(vi)). The process of applying for an entry clearance will allow you to sort out with the Consulate exactly what you do and do not need, and whether or not you qualify.
Usual disclaimers: This is not formal legal advice and is not intended to be relied on, etc etc. If in any doubt, you should get your own legal advice tailored to the facts of your case from someone who's in a position to take full instructions from you.