[1][2] According to Livy,[3] and Dionysius of Halicarnassus,[4] he was the brother of Lucius Cornelius Maluginensis Uritus Cossus (consul in 459 BC) but his name would be the same as his father if we refer to the filiation given by the Fasti Capitolini.
[1] At the instigation of Appius Claudius, the decemvirs illegally held onto power the following year, refusing to proceed with the election of consuls.
Meanwhile, Appius Claudius and Spurius Oppius Cornicen remained in Rome to ensure the defence of the city, and the four other decemvirs fought against the Sabines.
The army commanded by Marcus Cornelius had withdrawn to Tusculum then moved in response to the call from Lucius Verginius, whose daughter had been enslaved by Appius Claudius.
Under their command, they returned to Rome and set up camp on the Aventine and were then joined by the other Roman army that was led by Appius Claudius and Spurius Oppius Cornicen.