He succeeded his father, Arnulf, in East Francia and his elder illegitimate half-brother Zwentibold in Lotharingia.

He was the only legitimate son of king Arnulf of Carinthia and his wife, Ota, a member of the Conradine dynasty.

Louis was of a weak personal constitution, often sick, and due to his young age, the reins of government were entirely in the hands of others – the nobles and bishops.

It was these two who assured that the royal court decided in favour of the Conradines against the Babenbergers in the matter of the Duchy of Franconia.

In 907 they inflicted a heavy defeat on the Bavarians who had invaded Hungary, killing the Margrave Luitpold and many high nobles in the Battle of Pressburg.

In a state of despair, possibly afflicted by severe depression, Louis died at Frankfurt am Main on 20 or 24 September 911, seventeen or eighteen years old.