Okay, I feel a little stupid asking this, but I'm contemplating a maritime historical novel, and I was just wondering if anyone could answer some questions on the use of ensigns by the British Royal Navy in the early nineteenth century (i.e. Napoleonic Wars era).

Basically, what I want to know is:

What was the purpose of each of the red, white and blue ensigns?

When going into battle, would they be flown from the mast rather than the stern, as a battle flag, or would the Union Jack perform that function?


Thanks for any help, the Admiralty procedures from that time period confuse the hell out of me :p