Answer:
Charlemagne's death in 814 began an extended period of fragmentation and decline of the dynasty that would eventually lead to the evolution of the territories of France and Germany.
Step-by-step explanation:
Charlemagne, who was crowned Emperor by Pope Leo III at Rome in 800, was the greatest Carolingian monarch. His empire, ostensibly a continuation of the Roman Empire, is referred to historiographically as the Carolingian Empire. The traditional Frankish (and Merovingian) practice of dividing inheritances among heirs was not given up by the Carolingian emperors, though the concept of the indivisibility of the Empire was also accepted. The Carolingians had the practice of making their sons minor kings in the various regions (regna) of the Empire, which they would inherit on the death of their father.
Following the death of Louis the Pious (Charlemagne’s son), the surviving adult Carolingians fought a three-year civil war ending only in the Treaty of Verdun, which divided the empire into three regna while according imperial status and a nominal lordship to Lothair I. By this treaty, Lothair received northern Italy and a long stretch of territory from the North Sea to the Mediterranean, essentially along the valleys of the Rhine and the Rhône; this territory includes the regions of Lorraine, Alsace, Burgundy, and Provence. He soon ceded Italy to his eldest son, Louis, and remained in his new kingdom, engaging in alternate quarrels and reconciliations with his brothers and in futile efforts to defend his lands from the attacks of the Northmen (as Vikings were known in Frankish writings) and the Saracens.
The Carolingians differed markedly from the Merovingians in that they disallowed inheritance to illegitimate offspring, possibly in an effort to prevent infighting among heirs and assure a limit to the division of the realm. In the late 9th century, however, the lack of suitable adults among the Carolingians necessitated the rise of Arnulf of Carinthia, an illegitimate child of a legitimate Carolingian king.
The Carolingians were displaced in most of the regna of the Empire in 888. They ruled on in East Francia until 911 and held the throne of West Francia intermittently until 987. Carolingian cadet branches continued to rule in Vermandois and Lower Lorraine after the last king died in 987, but they never sought thrones of principalities, and they made peace with the new ruling families. One chronicler dates the end of Carolingian rule with the coronation of Robert II of France as junior co-ruler with his father, Hugh Capet, thus beginning the Capetian dynasty. Capet’s descendants—the Capetians, the House of Valois, and the House of Bourbon—progressively unified the country through wars and dynastic inheritance into the Kingdom of France, which was fully declared in 1190 by Philip II Augustus. Thus West Francia of the Carolingian dynasty became France.
Following the breakup of the Frankish Realm, the history of Germany was for 900 years intertwined with the history of the Holy Roman Empire, which subsequently emerged from the eastern portion of Charlemagne’s original empire. The territory initially known as East Francia stretched from the Rhine in the west to the Elbe River in the east, and from the North Sea to the Alps. Germany as we know it today did not come into existence until after WWI when the various principalities of the region were united as a modern nation-state.
The Carolingian dynasty became extinct in the male line with the death of Eudes, Count of Vermandois. His sister Adelaide, the last Carolingian, died in 1122.