Alamannia, or Alemania, was the kingdom established and inhabited by the Alemanni, a Germanic tribal confederation that had broken through the Roman limes in 213.
The Alemanni expanded from the Main River basin during the 3rd century and raided Roman provinces and settled on the left bank of the Rhine River from the 4th century.
The Alemanni or Alamanni were a confederation of Germanic tribes on the Upper Rhine River during the first millennium. First mentioned by Cassius Dio in the context of the campaign of Roman emperor Caracalla of 213 CE, the Alemanni captured the Agri Decumates in 260, and later expanded into present-day Alsace and northern Switzerland, leading to the establishment of the Old High German language in those regions, which by the eighth century were collectively referred to as Alamannia.
In 496, the Alemanni were conquered by the Frankish leader Clovis and incorporated into his dominions. Mentioned as still pagan allies of the Christian Franks, the Alemanni were gradually Christianized during the seventh century. The Lex Alamannorum is a record of their customary law during this period. Until the eighth century, Frankish suzerainty over Alemannia was mostly nominal. After an uprising by Theudebald, Duke of Alamannia, however, Carloman executed the Alamannic nobility and installed Frankish dukes.
The Franks, Germanic peoples that invaded the Western Roman Empire in the 5th century, were first led by individuals called dukes and reguli. The earliest group of Franks that rose to prominence was the Salian Merovingians, who conquered most of Roman Gaul, as well as the Gaulish territory of the Visigothic Kingdom, following the Battle of Vouillé in 507 AD.
The sons of Clovis I, the first King of the Franks, conquered the Burgundian and the Alamanni Kingdoms. They acquired Provence, and went on to make the peoples of the Bavarii and Thuringii their clients. The Merovingians were later replaced by the new Carolingian dynasty in the 8th century. By the late 10th century, the Carolingians themselves had been replaced throughout much of their realm by other dynasties.
Charles the Fat (839 – 13 January 888) was the emperor of the Carolingian Empire from 881 to 887. A member of the Carolingian dynasty, Charles was the youngest son of Louis the German and Hemma, and a great-grandson of Charlemagne. He was the last Carolingian emperor of legitimate birth and the last to rule a united kingdom of the Franks.
Over his lifetime, Charles became ruler of the various kingdoms of Charlemagne's former empire. Granted lordship over Alamannia in 876, following the division of East Francia, he succeeded to the Italian throne upon the abdication of his older brother Carloman of Bavaria who had been incapacitated by a stroke. Crowned emperor in 881 by Pope John VIII, his succession to the territories of his brother Louis the Younger (Saxony and Bavaria) the following year reunited the kingdom of East Francia. Upon the death of his cousin Carloman II in 884, he inherited all of West Francia, thus reuniting the entire Carolingian Empire.
Louis the Younger (830/835 – 20 January 882), sometimes called Louis the Saxon or Louis III, was the second of three sons of king Louis the German and queen Hemma, with his brothers being the elder Carloman and younger Charles. They all succeeded their father as kings in Eastern Francia on 28 August 876, in accordance with the prearranged partition, with Carloman ruling over Bavaria and the Pannonian March, Louis over Franconia, Saxony and Thuringia, and Charles over Alamannia. Louis and Charles also jointly ruled over eastern parts of Lotharingia. In 879-880, Louis acquired the western part of Lotharingia. In 880, Carloman died and his realm was inherited by Louis. By 881, the youngest brother Charles secured rule over Italy, and was crowned as emperor. Louis died in 882, without legitimate descendants, and was succeeded in all his territories, which encompassed most of East Francia, by his brother Charles.