Complex sentence: When Roger and Mary Williams arrived at Boston on February 5,1631, he was welcomed and almost immediately invited to become the Teacher minister in the Boston church to officiate while Rev. John Wilson returned to England to fetch his wife.
Split into simpler sentences: When Roger and Mary Williams arrived at Boston on February 5,1631, he was welcomed. Almost immediately, the Boston church invited Rev. Williams to become their Teacher minister, to officiate while Rev. John Wilson returned to England to fetch his wife.