Lotharingia in the context of "Treaty of Meerssen"

Lorraine is a historical area of Eastern France that today falls within the administrative region of Grand Est. It was the medieval kingdom called Lotharingia (855–959 AD), after Emperor Lothair I or King Lothair II, which extended further north and came to be ruled by the Holy Roman Empire as the Duchy of Lorraine, before the Kingdom of France annexed it in 1766.

From 1982 until January 2016, Lorraine was an administrative region of France. In 2016, under a reorganisation, it became part of the new region Grand Est. As a region in modern France, Lorraine consisted of the four departments Meurthe-et-Moselle, Meuse, Moselle and Vosges (from a historical point of view the Haute-Marne department is also located in the region), containing 2,337 communes. Metz is the regional prefecture. The largest metropolitan area of Lorraine is Nancy, which was the seat of the duchy for centuries.

The Duchy of Burgundy (/ˈbɜːrɡəndi/; Latin: Ducatus Burgundiae; French: Duché de Bourgogne) was a medieval and early modern feudal polity in north-western regions of historical Burgundy. It was a duchy, ruled by dukes of Burgundy. The Duchy belonged to the Kingdom of France, and was initially bordering the Kingdom of Burgundy to the east and south, thus being distinct from the neighboring Free County of Burgundy (modern region of Franche-Comté). The first duke of Burgundy (Latin: dux Burgundiae), attested in sources by that title, was Richard the Justiciar in 918.

In 1004, prince Henry of France, a son of king Robert II of France, inherited the Duchy, but later ceded it to his younger brother Robert in 1032. Robert became the ancestor of the ducal House of Burgundy, a cadet branch of the royal Capet dynasty, ruling over a territory that roughly conformed to the borders and territories of the modern region of Burgundy (Bourgogne). Upon the extinction of the Burgundian male line with the death of Duke Philip I in 1361, the duchy reverted to King John II of France and the royal House of Valois. The Burgundian duchy was absorbed in a larger territorial complex after 1363, when King John II ceded the duchy to his younger son Philip. With his marriage with Countess Margaret III of Flanders, he laid the foundation for a Burgundian State which expanded further north in the Low Countries collectively known as the Burgundian Netherlands. Upon further acquisitions of the County of Burgundy, Holland, and Luxemburg, the House of Valois-Burgundy came into possession of numerous French and imperial fiefs stretching from the western Alps to the North Sea, in some ways reminiscent of the Middle Frankish realm of Lotharingia.

Lothair II (835 – 8 August 869) was a Carolingian king and ruler of northern parts of Middle Francia, that came to be known as Lotharingia, reigning there from 855 until his death in 869. He also ruled over Burgundy, holding from 855 just the Upper regions, and from 863 also the Lower Burgundy. He was the second son of Emperor Lothair I and Ermengarde of Tours. He was married to Teutberga (died 875), daughter of Boso the Elder.

The Duchy of Lorraine was a principality of the Holy Roman Empire which existed from the 10th century until 1766 when it was annexed by the Kingdom of France. It gave its name to the larger present-day region of Lorraine in northeastern France. Its capital was Nancy.

It was founded in 959 following the division of Lotharingia into two separate duchies: Upper and Lower Lorraine, the westernmost parts 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 was coveted and briefly occupied by the dukes of Burgundy and the kings of France, but was ruled by the dukes of the House of Lorraine after 1473.

The Burgundian State (French: État bourguignon [eta buʁɡiɲɔ̃]; Dutch: Bourgondische Rijk [burˈɣɔndisə ˈrɛik]) was a composite monarchy ruled by the Dukes of Burgundy from the late 14th to the late 15th centuries, and which ultimately comprised not only the Duchy and County of Burgundy but also the Burgundian Netherlands. The latter, acquired piecemeal over time and largely through inheritance, was, in fact, their principal source of wealth and prestige. The Dukes were members of the House of Valois-Burgundy, a cadet branch of the French royal House of Valois, and the complex of territories they ruled is sometimes referred to as Valois Burgundy. The term "Burgundian State" was coined by historians and was not in contemporary use; the polity remained a collection of separate duchies and counties in personal union under the Duke of Burgundy.

It is regarded as one of the major powers in Europe of the 15th century. The Dukes of Burgundy were among the wealthiest and the most powerful princes in Europe and were sometimes called "Grand Dukes of the West". Including the thriving regions of Flanders and Brabant, the Burgundian State was a major centre of trade and commerce and a focal point of courtly culture that set the fashion for European royal houses and their courts. It nearly turned into a kingdom in its own right, but Charles the Bold's early death at the Battle of Nancy put an end to his Lotharingian dream and his legacy passed to the House of Habsburg through the marriage of his daughter Mary to Maximilian of Austria. Meanwhile Picardy and the Duchy of Burgundy were conquered by the King of France.

Louis the German (German: Ludwig der Deutsche; c. 806/810 – 28 August 876), also known as Louis II of Germany (German: Ludwig II. von Deutschland), was the first king of East Francia, and ruled from 843 to 876 AD. Grandson of emperor Charlemagne and the third son of Louis the Pious, emperor of Francia, and his first wife, Ermengarde of Hesbaye, he received the appellation Germanicus shortly after his death, when East Francia became known as the kingdom of Germany.

After protracted clashes with his father and his brothers, Louis received the East Frankish kingdom in the Treaty of Verdun (843). His attempts to conquer his half-brother Charles the Bald's West Frankish kingdom in 858–59 were unsuccessful. The 860s were marked by a severe crisis, with the East Frankish rebellions of the sons, as well as struggles to maintain supremacy over his realm. In the Treaty of Meerssen he acquired Lotharingia for the East Frankish kingdom in 870. On the other hand, he tried and failed to claim both the title of Emperor and Italy. In the East, Louis was able to reach a longer-term peace agreement in 874 after decades of conflict with the Moravians. His rule shows a marked decline in creation of written administration and government documents, a trend that would continue into Ottonian times.