Complex sentence: There were twelve of them, one being Captain Davis--who graduated from the United States Military Academy in 1936, the first black graduate there in forty-seven years after having been "silenced" there for four years.
Split into simpler sentences: There were twelve of them, one being Captain Davis, who graduated from the United States Military Academy. In 1936, the first black graduate there in forty-seven years after having been "silenced" there for four years.