Complex sentence: The Industrial Union Party (IUP), a US DeLeonist political organization, proclaimed itself on 7 July 1933 at 1032 Prospect Avenue, Bronx, Branch headquarters of its predecessor Industrial Union League (IUL).
Split into simpler sentences: The Industrial Union Party (IUP) was a US DeLeonist political party. The party proclaimed itself on 7 July 1933 at 1032 Prospect Avenue, Bronx, Branch headquarters of its predecessor Industrial Union League (IUL).