Detailed Instructions: In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.
Q: This man resigned from his position where he directed the operations of the Black Hawk wars in order to become "Envoy Extraordinaire and Minister Plenipotentiary to France. " In 1849, he was elected to fill his own vacancy in the senate, and he resigned as ambassador to France in the wake of the Webster-Ashburton treaty, after writing the pamphlet "An Examination of the Questions now in Discussion between the American and British Government Concerning the Right of Search" in response to the Quintuple treaty negotiations between Austria, Russia, France, Britain, and Prussia to suppress the slave trade. This man lost support in his bid for the presidency due to the defection of the barnburners, and he claimed in the "Nicholson letter" that states should decide for themselves whether to allow slavery. An opponent of the Wilmot Proviso, for 10 points, name this senator from Michigan who was an early proponent of Popular Sovereignty.
A:
History