The British caused immense damage to Sikhs after they took over the Punjab in 1845. A British scholar in 1881 stated Punjab had a education system far superior then the Europeans and the capital Lahore had the most scholars in the world.
The British knew if they were to control Punjab for years to come, they must hurt the Sikhs at the core. They started off with burning books and preaching the Christian faith.
An incident which occurred in 1848 was a direct attack on the Sikh faith. The British officers and officials walked inside Sri Harimandir Sahib with their shoes on. The Akal Takht Jathedar Ganda Singh, Akali Kharak Singh, Bibek Singh, Hira Singh, Mastan Singh, Muhar Singh, and Hukam Singh protested the sacrilege which resulted in a clash causing the death of one of the government officials.
During the clash, many Sikhs were injured and then arrested. The British tyrant Mr. Lawrence arrested the protesting Sikhs and Akal Takht Jathedar Ganda Singh and 2 other Sikhs were hanged and 6 were sent to Jails outside Punjab.
Source “Sri Amritsar Ji De Darshan Ishnan Ate 500 Salan Di Itihask Directory”