In 1814, he was in the 15e régiment de tirailleurs:
http://www2.culture.gouv.fr/LH/LH260/PG/FRDAFAN83_OL2471009V004.htm
Several sources (Google snippet view or preview) place Savarin in Saint-Denis, not in Montmartre. Here is one:
https://books.google.de/books?id=k-Q3DwAAQBAJ