Lac Daumesnil is a lake in Paris, France. Its surface area is 0.12 km²
The Paris region was under full control of the Germanic Franks by the late 5th century. The Frankish king Clovis the Frank, the first king of the Merovingian dynasty, made the city his capital from 508. The late 8th century Carolingian dynasty displaced the Frankish capital to Aachen; this period coincided with the beginning of Viking invasions that had spread as far as Paris by the early 9th century.
Repeated invasions forced Parisians to build a fortress on the Île de la Cité. One of the most remarkable Viking raids was on 28 March 845, when Paris was sacked and held ransom, probably by Ragnar Lodbrok, who left only after receiving a large bounty paid by the crown. The weakness of the late Carolingian kings of France led to the gradual rise in power of the Counts of Paris; Odo, Count of Paris, was elected king of France by feudal lords, and the end of the Carolingian empire came in 987 when Hugh Capet, count of Paris, was elected king of France. Paris, under the Capetian kings, became a capital once more.