Viktor Külföldi, real name Jakab Mayer-Rubcsics, born Jacob Mayer () (1844 March 5, 1894) was a Hungarian Socialist, journalist, and lecturer.
Born in Thalheim, Germany (or Switzerland?), he was known in his adopted country by the alias (Hungarian for "foreigner"). In 1871 he became a member of the International Working Men's Association. Together with (1842–1907) and , he co-founded the first Hungarian Socialist organization, the (). For organizing a strike by the GWMU, he, among others, was arrested (18712) and accused of high treason; he was eventually acquitted because of lack of evidence.
In 1877 Külföldi founded the Social-democratic newspaper ("People's Voice"). He retired from the worker's movement in 1890 and died in Budapest in 1894.
Publications
References