Udham Singh (26 December 1899 – 31 July 1940) was an Indian rebel for the Ghadar Party and the HSRA, best known for the assassination of Michael O’Dwyer, a lieutenant colonel of the Punjab in India, on March 13, 1940.

His assassination was carried out in retaliation for the Jallianwala Bagh massacre in Amritsar in 1919, O’Dwyer was in charge.

Singh was subsequently prosecuted and convicted of murder and hanged in July 1940.

While in custody he used the name Ram Mohammad Singh Azad, representing the three major Indian religions and his anti-colonial sentiments.

Udham Singh is a well-known figure in the Indian liberation movement.

He is also called Shaheed-i-Azam Sardar Udham Singh (the word “Shaheed-i-Azam”, meaning “great martyr”).

The Uttarakhand district (Udham Singh Nagar) was named after him in October 1995 by the Mayawati government.