Original sentence: The opposition members (who included the former prime minister Wincenty Witos, and the Wojciech Korfanty) were imprisoned in the Brest Fortress, where their trial took place (thus the popular name for the election: the 'Brest election')
Edited sentence: The opposition members (who included the former prime minister Wincenty Witos, and the Silesian national hero, Wojciech Korfanty) were imprisoned in the Brest Fortress, where their trial took place (thus the popular name for the election: the 'Brest election')