In 1804, he entered into alliance with Lord Lake against Jasvant Rao Holkar. In 1805, Raja Jasvant Singh in company with Raja Bhag Singh of Jind appealed to Maharaja Ranjit Singh to arbitrate his dispute with Patiala and though the dispute was not resolved, Jasvant Singh was able to extend Ins territory with grants from Ranjit Singh. Despite these favours, Jasvant Singh joined hands with the other Sutlej princes under the treaty of 1809. Jasvant Singh helped the British in the Gurkha war in 1814 as well as in the Kabul campaign in 1838.
Raja Jasvant Sirigli was a popular prince much loved by his subjects. Writing about him, Sir David Ochtcrlony, British diplomat and soldier, said, "Jaswant Singh is one of the principal Sirdars under our protection and by far superior in manner, management, and understanding to any of them I have yet seen." Sir Lcpcl Griffin considered him "the nearest approach to the civi li/cd among the whole set of rude barons." Raja Jasvant Sirigli died at Nabha on 22 May 1840.
1. GritTin, Lcpel, I`he Rajas of the Punjab [Reprint]. Delhi, 1977
2. Ganda Singh, The Patiala and East Punjab Suites Union. Patiala, 1951