Conversation so far:
Where did Guy Carleton reside post-war?
Quebec
What did Guy Carleton do in Quebec?
Guy Carleton was appointed Governor-in-chief.
Did Guy Carleton do anything notable while Governor-in-chief?
Guy Carleton was mostly ignored.
What did Guy Carleton do after his position as Governor-in-chief?
Guy Carleton was raised to the Peerage in August 1786 as Lord Dorchester, Baron of Dorchester in the County of Oxford.

Question: How long was he there?
Self-contained rewrite: How long was Guy Carleton in Quebec?