Complex sentence: Dawes resumed a role in the banking business, becoming chairman of the board of the City National Bank and Trust Co. from 1932 until his death in Evanston in 1951.
Split into simpler sentences: Dawes resumed a role in the banking business. He served for nearly two decades as chairman of the board of the City National Bank and Trust Co., from 1932 until his death in Evanston in 1951.