It was founded in 959 as a result of the division of the kingdom of Lotharingia in two separate duchies: Lower Lorraine and Upper Lorraine, both duchies forming the western part of the Holy Roman Empire. The Lower duchy was quickly dismantled, while Upper Lorraine came to be known as simply the Duchy of Lorraine. The Duchy of Lorraine lost many territories, like the Three Bishoprics or the county of Bar and was coveted and briefly occupied by the Dukes of Burgundy and the Kings of France.
In 1737, the Duchy was given to Stanisław Leszczyński, the former king of Poland who had lost his throne as a result of the War of the Polish Succession, with the understanding that it would fall to the French crown upon his death. When Stanisław died on 23 February 1766, Lorraine was annexed by France and reorganized as a province.
Lorraine's predecessor Lotharingia was an independent Carolingian kingdom under the rule of King Lothair II (855–869). Its territory had originally been a part of Middle Francia, created in 843 by the Treaty of Verdun, when the Carolingian empire was divided between the three sons of Louis the Pious. Middle Francia was allotted to Emperor Lothair I, therefore called Lotharii Regnum. Upon his death in 855, it was further divided into three parts, of which his son Lothair II took the northern one. His realm then comprised a larger territory stretching from the County of Burgundy in the south to the North Sea. In French, this area became known as Lorraine, while in German, it was eventually known as Lothringen. In the Alemannic language once spoken in Lorraine, the -ingen suffix signified a property; thus, in a figurative sense, "Lotharingen" can be translated as "Land belonging to Lothair".
As Lothair II had died without heirs, his territory was divided by the 870 Treaty of Meerssen between East and West Francia and finally came under East Frankish rule as a whole by the 880 Treaty of Ribemont. After the East Frankish Carolingians became extinct with the death of Louis the Child in 911, Lotharingia once again attached itself to West Francia, but was conquered by the German king Henry the Fowler in 925. Stuck in the conflict with his rival Hugh the Great, King Louis IV of France in 942 renounced all claims to Lotharingia.
Duchy of Upper Lorraine
In 953 the German king Otto I had appointed his brother Bruno the Great Duke of Lotharingia. In 959, Bruno divided the duchy into Upper and Lower Lorraine which became permanent following his death in 965. The Upper Duchy was further "up" the river system, that is, it was inland and to the south. Upper Lorraine was first denominated as the Duchy of the Moselle, both in charters and narrative sources, and its duke was the dux Mosellanorum. The usage of Lotharingia Superioris and Lorraine in official documents begins later, around the fifteenth century. The first duke and deputy of Bruno was Frederick I of Bar, son-in-law of Bruno's sister Hedwig of Saxony.
The border between the Empire and the Kingdom of France remained relatively stable throughout the Middle Ages. In 1301 Count Henry III of Bar had to receive the western part of his lands (Barrois mouvant) as a fief by King Philip IV of France. The Burgundian duke Charles the Bold in 1475 campaigned for the Duchy of Lorraine, but finally was defeated and killed at the 1477 Battle of Nancy. In 1552 a number of insurgent Protestant Imperial princes around Elector Maurice of Saxony by the Treaty of Chambord ceded the Three Bishoprics to King Henry II of France in turn for his support.
Between France and Germany
Lorraine remained a part of France, but its northern part known as Moselle, along with Alsace, largely German-speaking regions, were annexed by the newly founded German Empire, following the Franco-Prussian War, and French language was forbidden. The territories were not annexed by any state of the Empire or organised into a separate state, but were governed as the Reichsland Elsass-Lothringen under a governor directly appointed by the German Emperor. Alsace-Lorraine remained a part of Germany until after the end of World War I, when France occupied the area and annexed it. Policies forbidding the use of German and requiring that of French were then begun, as well as expulsions of Germans who had moved to the region after 1871.
In 1940, Nazi Germany re-annexed Alsace-Lorraine during World War II combining Moselle with the Saarland and Alsace with Baden. The French language was again proscribed and education at German schools made compulsory. The war-torn area returned to France in November 1944. Because of the fighting in the area, Lorraine is home to the Lorraine American Cemetery and Memorial, the largest American war cemetery in France.