Romans to abandon the linear defence concept. The Swiss Plateau was finally open to Germanic tribes. In the Early Middle Ages, from the end of the fourth century, the western extent of modern-day Switzerland was part of the territory of the Kings of the Burgundians. The Alemanni settled the Swiss Plateau in the fifth century and the valleys of the Alps in the eighth century, forming Alemannia. Modern-day Switzerland was then divided between the kingdoms of Alemannia and Burgundy. The entire region became part of the expanding Frankish Empire in the sixth century, following Clovis I's victory over the Alemanni at Tolbiac in 504 AD, and later Frankish domination of the Burgundians. Throughout the rest of the sixth, seventh and eighth centuries, Swiss regions continued under Frankish hegemony (Merovingian and Carolingian dynasties) but after its extension under Charlemagne, the Frankish Empire was divided by the Treaty of Verdun in 843. The territories of present-day Switzerland became divided into Middle Francia and East Francia until they were reunified under the Holy Roman Empire around 1000 AD. By 1200, the Swiss Plateau comprised the dominions of the houses of Savoy, Zähringer, Habsburg, and Kyburg. Some regions (Uri, Schwyz, Unterwalden, later known as ) were accorded the Imperial immediacy to grant the empire direct control over the mountain passes. With the extinction of its male line in 1263, the Kyburg dynasty fell in AD 1264. The Habsburgs under King Rudolph I (Holy Roman Emperor in 1273) laid claim to the Kyburg lands and annexed them, extending their territory to the eastern Swiss Plateau. Old Swiss Confederacy The Old Swiss Confederacy was an alliance among the valley communities of the central Alps. The Confederacy was governed by nobles and patricians of various cantons who facilitated management of common interests and ensured peace on mountain trade routes. The Federal Charter of 1291 is considered the confederacy's founding document, even though similar alliances likely existed decades earlier. The document was agreed among the rural communes of Uri, Schwyz, and Unterwalden. By 1353, the three original cantons had joined with the cantons of Glarus and Zug and the Lucerne, Zürich and Bern city-states to form the "Old Confederacy" of eight states that obtained through the end of the 15th century. The expansion led to increased power and wealth for the confederation. By 1460, the confederates controlled most of the territory south and west of the Rhine to