Emile Acollas (French: [akɔla]; 25 June 1826, La Châtre – 17 October 1891, Asnières) was a French professor of jurisprudence born in La Châtre, Indre and educated in Bourges and Paris.
He was one of the founders of the League of Peace and Freedom set up in 1867. His call for the conference gained 10,000 adherents including Victor Hugo, John Stuart Mill, Elisée Reclus, Giuseppe Garibaldi, Louis Blanc and Mikhail Bakunin. Karl Marx was dismissive and urged the newly formed International Workingmen's Association to have no official involvement. Acollas insisted that the first Conference, held in Geneva, should be called a "revolutionary conference". At the subsequent conference held in 1869 in Lausanne, Acollas attacked the very idea of monarchy. But the League was to collapse with the outbreak of the Franco-Prussian War.
In 1870 Acollas had the post at the University of Berne, when the Paris Commune appointed him Dean of the Law Faculty of the University of Paris. However he never took up the post and avoided any recriminations, returning to Paris in 1871. He set up the Acollas Law School primarily for foreign students wishing to attend the University of Paris.