Banda Singh Bahadur's invasion of the Hill States

The first Hill State Banda focused was on Kahlur. The main reason of Kahlur becoming the first target was because of Kahlur always being a key enemy to Guru Gobind Singh.[3][4] A messenger was sent to the Raja of Kahlur to ask him to submit.[5] Both parties had a meeting in which they made discussions about a battle and what they would do it they won. Right after the discussion, the Raja of Kahlur placed as many troops as possible to defend the Kahlur Fort. The fort was guarded by 1300 Mian Caste Rajputs with 7 war elephants.[1][5][6] Banda Singh sent 5 Sikhs to the battlefield who were accompanied voluntary by a large number of Sikhs. Bhai Kehar Singh, Bhai Ranjit Singh and Baba Ranjor Singh finished all 7 of the war elephants. Bhai Bajar Singh marched towards the fort and brought down both of its doors. Baba Baghar Singh cleared the passage through enemy columns and destroyed the forces which were blocking the entrance of the fort. During all this time, the Khalsa reinforcements had arrived. Kahlur was defeated with 1,300 troops dead.[1][3][5][7][8] Bilaspur's immense booty was looted by the Sikhs.[9] This defeat also spread terror among other hill Rajas, forcing most of them to submit to the Sikhs. Many of them went to the Sikh camp to greet them and offer them allegiance and to pay tribute to the Sikh treasury.[5]

The Raja of Mandi Sudh Sain was informed that Banda Singh was about to attack Mandi next. The raja declared himself the follower of Guru Nanak and gave in marriage a girl from his own family.[1][10] D.S Saggu says that Banda met his wife Bibi Susheel Kaur at Jammu, Surjit Gandhi states that it was Chamba and Rattan Singh Bhangu states that it was Mandi.[6]

Banda Singh Bahadur wanted to visit the famous shrine of Mahesh at Kullu and also wanted to pay a visit to the various Sidhas. However, when Banda Singh stepped into the territory of Kullu, the Raja immediately arrested him.[1] The other Sikhs assisted by an enraged Sudh Sain launched a campaign to free Banda Singh. Banda Singh was freed and taught a lesson to the Raja of Kullu.[6]

Now the only raja who didn't submit to Banda Singh Bahadur was Raja Udai Singh of Chamba.[11] The Raja called his prime minister to strike a treaty with Banda by offering him tribute which Banda Singh agreed and accepted and in return received his blessings.