The Jallianwala Bagh Massacre occurred on April 13, 1919. It is one of the biggest massacres in the history of India during which British troops opened fire on a huge crowd of unarmed Indians in an open area known as the Jallianwala Bagh in Amritsar, Punjab. 

The Rowlatt Act, a repressive law passed by the British colonial government in 1919 that allowed them to imprison anyone suspected of sedition without trial, set the stage for the massacre. This act sparked widespread outrage throughout India, including in Punjab.