The Duchy of Lorraine was a historical region in northeastern France, established in the early Middle Ages. It was originally part of the larger territory of the Kingdom of Lotharingia, which was divided into several duchies. The duchy became prominent in the 11th century and was ruled by various noble families, including the House of Lorraine. In the 18th century, the duchy was absorbed into the French crown after the death of its last duke, Stanisław Leszczyński, who was also a former king of Poland. The region played a significant role in European politics and conflicts, particularly during the Thirty Years' War and the Franco-Prussian War.