The peace network War Resisters' International was founded in the Netherlands in 1921 and is nowadays based in London. Its statement of principles from 1924 included the declaration: "War is a crime against humanity. We therefore are determined not to support any kind of War and to strive for the removal of all the causes of War." The network's journal Bulletin (later changed to "War Resister" and since 1962 known as "War Resistance") was published in English, French, German, Russian and Esperanto.
Bulletin No. 1, First edition of the WRI's journal, 1923, photographer: Beyerw; source: Wikimedia Commons, https://commons.wikimedia.org/wiki/File:Wri_1923.jpg?, public domain.