Middle Ages:

A three-year civil war followed his death. By the Treaty of Verdun (843), a kingdom between the Rhine and Rhone rivers was created for Lothair to go with his lands in Italy, and his imperial title was recognised. Louis the German was in control of Bavaria and the eastern lands in modern-day Germany. Charles the Bald received the western Frankish lands, comprising most of modern-day France. Charlemagne's grandsons and great-grandsons divided their kingdoms between their descendants, eventually causing all internal cohesion to be lost.[N] In 987 the Carolingian dynasty was replaced in the western lands, with the crowning of Hugh Capet (r. 987996) as king.[O][P] In the eastern lands the dynasty had died out earlier, in 911, with the death of Louis the Child, and the selection of the unrelated Conrad I (r. 911918) as king.

Please answer a question about this article. If the question is unanswerable, say "unanswerable". How many years did the civil war after the death of Louis the Pious last?
three