Complex sentence: Henry van Wart (1784-1873), an American who became British by special act of Parliament, founded the Birmingham Stock Exchange and served as one of Birmingham's first Aldermen and a director of the Birmingham Banking Company.
Split into simpler sentences: Henry van Wart (1784-1873) was an American, but became British by special act of parliament. He was a businessman and politician, a founder of the Birmingham Stock Exchange, one of Birmingham's first Aldermen and a director of the Birmingham Banking Company.