Under the Carolingians, the Frankish kingdom spread to encompass an area including most of Western Europe; the east–west division of the kingdom formed the basis for modern France and Germany. Orman portrays the Treaty of Verdun (843) between the warring grandsons of Charlemagne as the foundation event of an independent France under its first king Charles the Bald; an independent Germany under its first king Louis the German; and an independent intermediate state stretching from the Low Countries along the borderlands to south of Rome under Lothair I, who retained the title of emperor and the capitals Aachen and Rome without the jurisdiction. The middle kingdom had broken up by 890 and partly absorbed into the Western kingdom (later France) and the Eastern kingdom (Germany) and the rest developing into smaller "buffer" nations that exist between France and Germany to this day, namely Benelux and Switzerland.