Many political parties and their leaders remained underground or in exile for the next 30 years of partyless politics in Nepal. BP Koirala was released from prison in 1968 and went into exile in Benaras, returning in 1976 only to immediately be put in house arrest. Although an armed insurgency launched by the major communist faction called the Jhapa movement had failed comprehensively by 1971, it formed the foundation for the dominant communist power, CPN ML, that was officially launched in 1978. A general referendum was held in 1980, which saw the CPN ML campaign for the option of multi-party democracy, along with Nepali Congress, but the Panchayat System was declared the winner to significant controversy. The Panchayat rule saw governments led by a group of monarchy loyalists taking turns, with Surya Bahadur Thapa, Tulsi Giri and Kirti Nidhi Bista becoming prime minister three times each, among others. It introduced a number of reforms, built infrastructures and modernised the country, while significantly curtailing political freedom, imposing the Nepali language and khas culture to the oppression of all others, and spreading Indophobic propaganda the effects of which are experienced to the present day.