] 1807-1809 Portland (Tory)
] 1809-1812 Perceval (Tory)
] 1812- 1827 Liverpool (Tory) becoming more liberal in policy after 1822.

I can't spot any direct references (and, believe me, I've looked) to the post-Pitt Tory administrations during which tiome JA's work came out. In general, these were a pretty uninspiring crew: repressive, and without any of Pitt's talent. Spencer Perceval, indeed, is famous for only one thing: he's the only British Prime Minister ever to have been assassinated (useful piece of trivia for quiz players).