After the death of the Raja of Jammu , Kishore Singh , in 1822 , his son Gulab Singh was recognized by the Sikhs as his heir .
During Sikh rule Jammu had been a tributary of the Sikh Empire in the Punjab region , but after the death of its Raja , Kishore Singh , Dogra , in 1822 his son Gulab Singh was recognized by the Sikhs as being his heir .