The results of a study of naturalizations in France are presented. This study supplements one concerning 3,000 French couples married between 1803 and 1832, whose patronymic descendants are reconstructed. The analysis centers on 515 naturalization files concerning people whose patronymic begins with the letters TRA for the period 1851-1939 and the analysis of the births and marriages of their children. The results indicate that by the second generation, 62 percent of the boys and 74 percent of the girls had married French nationals and that social class generally improved following marriage, indicating that assimilation of immigrants occurred effectively.