army and so

Question:

Who do i write to to find out if my ancestors served in the military/army and so forth?

i do not know if they did or not but if i know their D.o.b's full names and the area where they lived will i still be able to ask/find this out?

Names and addresses of who to to contact please
No silly Answers please also!

Additional Details

6 months ago
UK based sites and addresses only please

Best Answer - Chosen by Asker: 6 months ago
UK based sites and addresses only please