Family Compact, name popularly applied to a small, powerful group of men who dominated the government of Upper Canada (Ontario) from the closing years of the 18th cent. to the beginnings of responsible government under the Baldwin–LaFontaine Reform ministry (1848–51). The group, some of whose members belonged to the same family and most of whom were men of wealth, controlled the legislative and executive councils, had a virtual monopoly of political office, and strongly influenced banking, education, the issuing of land grants, the affairs of the Anglican church in Canada, and the courts. New settlers from Great Britain and the United States, finding themselves denied political opportunity, were drawn into an opposition movement, which in time became the Reform party. Religious differences embittered the struggle, since the Family Compact (the term first appeared c.1828) was composed almost entirely of members of the Church of England. The Château Clique was the name given to a similar powerful group in French Lower Canada.

See G. M. Craig, Upper Canada: The Formative Years, 1784–1841 (1963).

Family Compact, several alliances between France and Spain in the form of agreements between the French and Spanish branches of the Bourbon family. The first of the three compacts, the Treaty of the Escorial (1733), was continued and extended by the second agreement (1743). The third, and most important, of the treaties was that of 1761. Both England and France sought Spanish support in the Seven Years War, but England's attack on Spanish colonies and shipping alienated Charles III of Spain and the king rejected the English offer in favor of the proposal made by the French minister, the duc de Choiseul. The pact, which dealt with political and commercial relations and with the entry of Spain into the war, also included the Bourbon ruler of the Two Sicilies and the Infante Philip, duke of Parma. Spain entered the war (1762) but was of small use to France; the economic and political provisions of the pact proved more enduring than the military ones.