Udham Singh, a freedom fighter from India, assassinated Michael O'Dwyer, the former Lieutenant Governor of the Punjab province in India, in 1940 in revenge for the Jallianwala Bagh massacre of 1919.

The Jallianwala Bagh massacre was a tragic event in which British soldiers opened fire on a peaceful gathering of unarmed civilians in the Jallianwala Bagh garden in Amritsar, Punjab. The massacre resulted in the deaths of hundreds of people and caused outrage in India and around the world. Udham Singh, who was present at the massacre as a young boy, vowed to seek revenge and carried out the assassination of O'Dwyer, who was the Governor of Punjab at the time of the massacre, in London.