The Social Democrat Hunchakian Party (SDHP) (Սոցիալ Դեմոկրատ Հնչակյան Կուսակցություն; ՍԴՀԿ), is the oldest continuously-operating Armenian political party, founded in 1887 by a group of students in Geneva, Switzerland. It was the first socialist party to operate in the Ottoman Empire and in Iran, then known as Persia. Among its founders were Avetis Nazarbekian, Mariam Vardanian, Gevorg Gharadjian, Ruben Khan-Azat, Christopher Ohanian, Gabriel Kafian and Manuel Manuelian. Its original goal was attaining Armenia's independence from the Ottoman Empire during the Armenian national liberation movement.
The party is also known as Hentchak, Henchak, Social-Democratic Hentchaks, Huntchakians, Hnchakian, Henchags, and its name is taken from its newspaper Hunchak, meaning "clarion" or "bell". This is taken by party members to represent "a call or awakening, for enlightenment and freedom".
All seven founders of the party were Eastern Armenian Marxist students who had left Russian Armenia to further their education in various universities of Western Europe. They were young, in their twenties, and supported by their affluent bourgeois families. They were influenced by social-democratic revolutionary ideology, contacted Frederick Engels, Georgi Plekhanov and later Vladimir Lenin. Mariam Vardanian had worked with Russian revolutionaries in Saint Petersburg. For the purpose of furthering revolutionary activity in Turkish Armenia, they formed the Hunchakian Revolutionary Party in August, 1887. The party's manifesto, printed in the first issue of Hunchak journal, contained this slogan: "Those who cannot attain freedom through revolutionary armed struggle are unworthy of it".
The Hunchak party fought many battles against the Ottoman Empire, to free the Armenian people from Turkish rule. During this period, many famous intellectuals joined Hunchakian party, including Smpad Piurad, Stepan Sapah-Gulian, Alexander Atabekian, Atrpet and Aram Andonian.