Naina Singh Dhoot (1904-1989) played a pioneer role in the communist movement of the Indian subcontinent. He grew up in the Chenab Canal Colony, joined the Ghadar Party in Argentina and studied Marxism in Moscow. Returning to India in 1936, NSD established a night school at Calcutta for teaching Marxism. He revived the muzara movement in the Nili Bar and suffered police torture in the Lahore Fort. He guided major strikes of industrial workers in Jamshedpur, Amritsar and Okara. He strengthened the trade union movement of Kanpur in collaboration with R.D. Bhardwaj and S.S. Yusuf. He was imprisoned in the Deoli Detention Camp along with 260 leading communists. During the different phases of his political career, he worked in close association with Muzaffar Ahmad, Ajoy Kumar Ghosh and Harkishan Singh Surjeet. During the Partition, NSD led numerous campaigns for the prevention of communal riots and rehabilitation of refugees. Remaining underground for five years (1948-52) when the CPI was banned, he organized hundreds of workers at the Bhakra Dam site and led the muzara movement of Una to its logical end. Following the split of 1964, he joined the CPM and began to build the party from below. For nearly five decades, NSD remained involved in the struggles of the toiling masses, propagating Marxism and developing communist cadres. His personal experiences constitute an indispensable source for reconstructing the various political developments in the Indian subcontinent during the last century.