On 10 September 1919, the Treaty of Saint-Germain was signed, declaring the Austro-Hungarian monarchy dissolved. Negotiations over the future of the city were interrupted two days later when a force of Italian nationalist irregulars led by the poet Gabriele D'Annunzio part of the population. Because the Italian government, wishing to respect its international obligations, did not want to annex Fiume, D'Annunzio and the intellectuals at his side eventually established an independent state, the Italian Regency of Carnaro, a unique social experiment for the age and a revolutionary cultural experience in which various international intellectuals of diverse walks of life took part (like Osbert Sitwell, Arturo Toscanini, Henry Furst, Filippo Tommaso Marinetti, Harukichi Shimoi, Guglielmo Marconi, Alceste De Ambris, Whitney Warren and Léon Kochnitzky).