 At the age of twenty-three, he was posted to Saint-Domingue when the Haitian Revolution broke out in 1803 and a number of his relatives were killed.Joubert and his uncle, C. Joubert de Maine, fled first to Cuba and then to the United States.He eventually found his way to Baltimore, Maryland, where in 1805 he entered St. Mary's Seminary and was ordained a priest in 1810.