Complex sentence: Frederick Xavier Katzer (February 7,1844--July 23,1903) was an Austrian-born prelate of the Roman Catholic Church who served as the third bishop of the Diocese of Green Bay and the third Archbishop of the Archdiocese of Milwaukee in Wisconsin.
Split into simpler sentences: Frederick Xavier Katzer (February 7,1844--July 23,1903) was a Roman Catholic archbishop. Katzer was the third Bishop of Diocese of Green Bay and the third Archbishop of the Archdiocese of Milwaukee in Wisconsin.