How do I get King John to sign the Magna Carta?

Hint 1 of 14:

To get to Runnymeade, you'll need better transportation.

Hint 2 of 14:

That horse will do the trick.  Get on it.

Hint 3 of 14:

A messenger will come with word that John will be getting the
money he needs so he doesn't have to sign the Magna Carta.

Hint 4 of 14:

The messenger will have to come through the forest (SE of Runnymeade).