Analysis of information sources in references of the Wikipedia article "Kullu Dussehra" in English language version.
The story goes that a Vaishnav saint, Krishnadas, advised Raja Jagat Singh (1637-62) of Kullu to somehow obtain the idols of Lord Ram and Sita, which were enshrined in Ayodhya's Tretanath Temple, if he wished to be cured of leprosy.