Who betrayed Sikh Empire?

Tej Singh was a Sikh commander who was responsible for betraying the Sikh Empire, leading to its defeat at the hands of the British during the first Anglo-Sikh War.

Following Maharaja Rannjit Singh’s death, the Sikh court had become fractious, with each faction vying against each other. Tej Singh belonged to the faction loyal to Raja Gulab Singh of Jammu, who was against starting a war with the British. But he was ordered by Rani Jindan, mother of the reigning prince Duleep Singh to march against the British.

In the Battle of Sobraon, General Tej Singh crossed the pontoon bridge linking the two flanks of the Sutlej river and ordered its destruction. This led to the entrapment and destruction of the Sikh Army on the other side of the bank. Thus the battle ended in a British victory

For further reading check the following articles:

• Second Anglo-Sikh War
• British Raj
• First Anglo-Sikh War