The Ottoman Socialist Party () was founded by Hüseyin Hilmi, Namık Hasan, İbnül Tahir İsmail Faik, Baha Tevfik and Hamit Suphi on August 1910. İştirak became a periodical for the defense of socialism among Ottoman intellectuals. İştirak introduced different branches of socialism to its readers. It was the first time that the thoughts of Karl Marx were defended systematically in the Ottoman Press. The Ottoman Socialist Party was closed in 1912. After the assassination of Mahmut Şevket Pasha, Hilmi was exiled to Sinop Fortress Prison in 1913.
