Victor Adler was an Austrian politician, a leader of the labour movement and founder of the Social Democratic Workers' Party (SDAP).
Adler about 1900
Friedrich Adler (politician)
Friedrich Wolfgang "Fritz" Adler was an Austrian socialist politician, physicist, philosopher and journalist. He is perhaps best known for his assassination of Minister-President Karl von Stürgkh in 1916.
Friedrich Adler, about 1917