露仏同盟
Klotz was born in Paris to Alsatian Jewish parents. He was the nephew of Victor Klotz (1836–1906), a wealthy silk dealer. After completing his legal education, he enrolled as an advocate at the "Cour d'Appel" in Paris. In 1888, at the age of twenty, he founded "Vie Franco-Russe", an illustrated paper intended to increase popular support for the Franco-Russian Alliance. In 1892 he became editor of "Voltaire", and campaigned against the reactionary policy of Jules Ferry. In 1895, he founded "Français Quotidien", a patriotic daily paper devoted to national defense, into which "Voltaire" was later merged.