Complex sentence: He was an organizer of the Bank of Union County, Elk Point, South Dakota in 1943, and went on to serve as president and chairman of the board of the Bank of Union County from 1947 to 1958.
Split into simpler sentences: He was an organizer of the Bank of Union County, Elk Point, South Dakota in 1943. He would serve as President and chairman of the board, Bank of Union County, South Dakota from 1947 to 1958.