Shaheed Udham Singh (26 December 1899 – 31 July 1940) was a revolutionary belonging to the Ghadar Party, best known for his assassination in London of Michael O'Dwyer, the former lieutenant governor of the Punjab in India, on 13 March 1940. The assassination was in revenge for the Jallianwala Bagh massacre in Amritsar in 1919 for which O'Dwyer was responsible. Singh was subsequently tried and convicted of murder and hanged in July 1940. While in custody, he used the name Mohammad Singh Azad, which represents his anti-colonial sentiment.
Udham Singh is a well-known figure of the Indian independence movement. He is also referred to as Shaheed-i-Azam Sardar Udham Singh (the expression "Shaheed-i-Azam", means "the great martyr"). A district (Udham Singh Nagar) of Uttarakhand was named after him to pay homage in October 1995 by the then Mayawati government.
On 10 April 1919, a number of local leaders allied to the Indian National Congress including Satya Pal and Saifuddin Kitchlew were arrested under the Rowlatt Act. Protestors against the arrests were fired on by British troops, precipitating a riot. On 13 April, over twenty thousand unarmed People were assembled in Jallianwala Bagh, Amritsar to protest against the act. Udham Singh and his friends from the orphanage were serving water to the crowd.
Udham Singh became involved in revolutionary politics and was deeply influenced by Bhagat Singh and his revolutionary group. In 1924, Udham Singh became involved with the Ghadar Party, organising Indians overseas towards overthrowing colonial rule. In 1927, he returned to India on orders from Bhagat Singh, bringing 25 associates as well as revolvers and ammunition. Soon after, he was arrested for possession of unlicensed arms. Revolvers, ammunition, and copies of a prohibited Ghadar Party paper called "Ghadr-i-Gunj" ("Voice of Revolt") were confiscated. He was prosecuted and sentenced to five years in prison.
Upon his release from prison in 1931, Singh's movements were under constant surveillance by the Punjab police. He made his way to Kashmir, where he was able to evade the police and escape to Germany. In 1934, he reached London, where he found employment as an engineer. Privately, he formed plans to assassinate Michael O'Dwyer. In Singh's diaries for 1939 and 1940, he occasionally misspells O'Dwyer's surname as "O'Dyer", leaving a possibility he may have confused O'Dwyer with General Dyer.
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