
Spoiler alert:
He thought the villain was Severus Snape.
But it was actually Quirrell.

Answer: TreatyT of Hellgate (1855) Treaty of Medicine Creek (1854) Treaty of Neah Bay signed with the Makah (1855), Treaty of point Ellliot (1855), Point no point treaty (1855), Quinault treaty, Treaty of Walla Walla (1855)
Explanation: I added dates and some names, I hope this is ok.