Flaccus received Italy as his province when he was consul in 195 BC, and continued to wage war as proconsul the following year against the Gauls, with a victory over the Insubres at Mediolanum.
[4] In 191 Flaccus was a legate under Manius Acilius Glabrio in the war against the Aetolians and at the Battle of Thermopylae.
[5] In 190, Flaccus served on the three-man commission (triumviri coloniis deducendis) created to strengthen Placentia and Cremona.
The following year, the commission founded Bononia (modern Bologna) as a Roman colony (colonia).
Flaccus was a member of the College of Pontiffs from 196, when he succeeded Marcus Cornelius Cethegus, until his death.