Louis Jouvet did not receive an Oscar nomination for portraying the Baron in The Lower Depths.
Jouvet that night happens upon Pepel trying to make off with the baron's valuables. Jouvet is very enjoyable as he changes upon Pepel, as he expresses a bemusement above else since the baron has already lost everything due to debt collectors, and simply is not the type of man ideal to be robbed by the thief. The thief is forced to agree and instead of any conflict they just kinda hit it off. Jouvet and Gabin are great together as they create such an ease between the two creating the friendship in a surprisingly natural fashion. They happen to go even a step further as the two are just endearing together and it becomes rather fun to see them interact with one another. There is an abundance of warmth as the two actors brings such life to their time together. One of my favorite moments is when the baron allows Pepel to have his pick of a souvenir from his home, since he's lose it anyway, as Jouvet so well realizes this guy who just can't help but go with the flow despite it being so much against him.
After this point the baron loses most of his possessions leaving him to go to the same slum which Pepel hails from. Jouvet is again quite in realizing the oddly optimistic manner of baron as he goes to the Lower Depths almost eagerly despite having come from the upper crust. Jouvet in the lower depths presents the baron in an interesting fashion. He plays his scenes of entering the world almost a student of this life. He's not clearly as part of the scenery like so many of the other denizens, not far from Pepel actually although for different reasons, as he creates a certain distance. Jouvet does not play this as though the baron is above them or trying to be above them, rather he presents it as the baron is trying to learn the ropes of the life. Jouvet gives the baron an eagerness as he tries to make his place in his new world. Jouvet in his progressing scenes slowly portrays the gradual way Jouvet seems comfortable. What is perhaps most remarkable about it though is the way that he slowly loses a bit of his joyful personality just as he begins to becomes a man of the lower depths. This is not to say he becomes a wholly tragic, but Jouvet effectively displays how a man must change in his new environment. This is a good performance by Jouvet as his presence adds a nice bit of character essential for a film like this.