The Rowlatt Act was the legislation that aroused a wave of popular indignation and led to the massacre by the British at Jallianwala Bagh.

Overview of the Rowlatt Act:
The Rowlatt Act was a law passed by the British colonial government in India in 1919, which gave the authorities the power to detain people without trial and to arrest and search anyone suspected of sedition. It was named after Sir Sidney Rowlatt, the chairman of the committee that drafted the bill.

Reasons for Popular Indignation:
The Rowlatt Act was seen as a direct attack on the civil liberties of the Indian people, and it was widely protested by the Indian National Congress and other nationalist groups. The main reasons for popular indignation were:

- Violation of Civil Liberties: The Act violated the fundamental rights of the Indian people, such as the right to a fair trial and the right to free speech and assembly. It was seen as a tool to suppress political dissent and to stifle the growing nationalist movement in India.

- Lack of Consultation: The Act was passed without any consultation with the Indian people or their elected representatives. The Indian National Congress and other nationalist groups were not given a chance to express their views on the legislation.

- British Arrogance: The Act was seen as a manifestation of British arrogance and colonialism. It was seen as an attempt by the British to impose their will on the Indian people without any regard for their wishes or aspirations.

Jallianwala Bagh Massacre:
The popular protests against the Rowlatt Act culminated in the Jallianwala Bagh massacre, which took place on April 13, 1919, in Amritsar. A large crowd of unarmed protesters had gathered in Jallianwala Bagh to protest against the Act, and they were fired upon by British troops under the command of General Dyer. The massacre resulted in the deaths of at least 379 people and wounded over a thousand others.

Conclusion:
The Rowlatt Act and the Jallianwala Bagh massacre were defining moments in the history of India's struggle for independence. They galvanized the Indian people and led to a renewed sense of nationalism and unity. They also exposed the brutal and oppressive nature of British colonialism in India and paved the way for the eventual independence of the country.