|Lothair, rebel with a cause|
A mere two years after the first civil war, however, filial trouble reared its head again. Pepin of Aquitaine, still smarting from his treatment after rebelling a few years earlier, was summoned to his father's court, where he was treated so poorly that he departed without permission. Louis assumed Pepin would start trouble, and so he gathered an army to quell what he was certain was an imminent uprising. Louis declared the Aquitaine to be now the possession of Charles the Bald, his son by his second wife; the rest of his empire was promised to his eldest, Lothair. This move, however, did not satisfy Lothair. Not only was he bothered by seeing lands go to his half-brother, but he was also anxious that he not have to wait to rule it all.
Lothair had a friend in the pope, Gregory IV (ruled 827-844), whom he had helped establish on the Throne of Peter—a slap to his father, since the choice of pope was supposed to be ratified by the emperor.* Lothair asked Gregory to join him and help reconcile the hostile posturing between father and son. Pope Gregory joined Lothair, which annoyed the bishops who had sided with Louis. The conflict between the pope and bishops became as significant as that between the temporal lords, as they threatened to excommunicate each other.
Gregory spoke to Louis, returned to Lothair to continue negotiations, and was prevented by Lothair of returning to Louis. The appearance this created was that the pope was supporting Lothair rather than peace, and Louis' troops began to desert him. Louis, his wife Judith, and son Charles were all sent to house arrest in different locations.
In the formal procedure for deposing Louis and transferring all power to Lothair, however, the treatment of the one-time emperor was so demeaning that the nobles turned against Lothair. Louis returned to the throne in March 834, less than a year after his exile.
Where was Bernard in all this? He and the dispossessed Pepin had remained loyal to Louis. After the return of Louis to his throne, Bernard requested the return of his lands. Louis was conflicted, because he didn't want to annoy Berengar. Fortunately, fate intervened: Louis summoned both men to his court in June 835, and Berengar died on the way. Bernard was free to take back his lands.
Bernard had joined one civil war on the losing side, then one civil war on the losing side that turned out to be the winning side. There was a third option, however, and he would try it a few years later, in the free-for-all that followed the death of Louis.
*There was a fuss made, and Gregory needed to wait to be ratified by Louis, but Lothair's actions still rankled.