The House of Lorraine originated as a cadet branch of the House of Metz. It inherited the Duchy of Lorraine in 1473 after the death without a male heir of Nicholas I, Duke of Lorraine. By the marriage of Francis of Lorraine to Maria Theresa of Austria in 1736, and with the success in the ensuing War of the Austrian Succession (1740–1748), the House of Lorraine was joined to the House of Habsburg and became known as the House of Habsburg-Lorraine. Francis, his sons Joseph II and Leopold II, and his grandson Francis II were the last four Holy Roman emperors from 1745 until the dissolution of the empire in 1806. The House of Habsburg-Lorraine inherited the Habsburg Empire, ruling the Austrian Empire and then Austria-Hungary until the dissolution of the monarchy in 1918.

The Duchy of Lorraine, originally Upper Lorraine, was a duchy now included in the larger present-day region of Lorraine in northeastern France. Its capital was Nancy.