Royal Tea

They were loosing badly against the invaders. This was the sixth time Harry had died in the last year alone. It was time to try something new, a move of desperation. Maybe Death would be willing to let him try to go back and hold off the invasion? If nothing else it would lessen some of the paperwork the ancient immortal had to deal with.
Step 1: Get back in time, hopefully with a few helpers to prove he wasn't crazy
Step 2: Talk to the Muggle Queen
Step 3: Keep as many people alive as possible
This was going to be a nightmare but Harry wasn't still the Chosen One and the Master of Death for nothing. No matter how much he might hate it he was the last leader they had and he was damned well going to keep as many people alive as he possibly could to come out of the other side of this clusterfuck.