Complex sentence: He took his vows as a full member of the Congregation in Baltimore, Maryland in January 1842, and, after six years of difficult but fruitful work, he was appointed the Provincial Superior for the United States.
Split into simpler sentences: He took his vows as a member of the Congregation in Baltimore, Maryland, in January 1842. After six years of difficult but fruitful work, he was appointed as the Provincial Superior for the United States.