Pisacha kingdom refers to the territory of Pisachas who were a group of mountain dwellers lived in the mountains around the Kashmir Valley. These tribes were mentioned in the epic Mahabharata along with other exotic tribes. The Kashmiri language is considered to be a language in the group of Paisachi languages. Kasmiras and Pisachas were allies of the Kuru king Duryodhana . Some among them worshiped Duryodhana as a god.
References in Mahabharata
All Pisachas are said to be divided into innumerable classes (3:230). Pisachas were mentioned as a race distinct from Rakshasas, Daityas and Nagas at (1:227). A Pisacha king is mentioned as one among the Yakshas under the rule of Yaksha king Kubera:- Kustumvuru, Pisacha, Gajakarna, and Visalaka, Varaha-Karna, Tamraushtica, Falkaksha, and Falodaka; Hansachuda, Sikhavarta, Vibhishana, Pushpanana, Pingalaka, Sonitoda and Pravalaka; Vrikshavaspa-niketa, and Chiravasas—these and many other Yakshas by hundred and thousands always wait upon Kuvera (2:10). Ghatotkacha is mentioned as excelling (in strength and prowess) all Pisachas and kindred tribes as well as all Rakshasas (1:157). Ravana's army was composed of Rakshasas and Pisachas (3:283). Pisachas were part of the army of Karitikeya (3:228). Danavas and Yakshas and Rakshasas and Pisachas and Yatudhanas and Guhyakas were mentioned as separate tribes at (13:17).
The Parvatas, the Daserakas, the Kasmirakas, the Aurasikas, the Pisachas, the Samudgalas, the Kamvojas, the Vatadhanas were all mentioned togather at (7;11). A Pisacha woman is mentioned as linked with places like Yugandhara, Achutasthala, and Bhutilaya close to the Bahlika territories in the north west of India (3:129). Pisachas, Nagas and Rakshasas were mentioned as inhabitants of the Khandava forest (1:230). There on the banks of Saraswati River dwell Yakshas, and Vidyadharas, and Rakshasas of immeasurable energy and Pisachas of immeasurable might, and Siddhas, numbering thousands (9:37). Beyond the Himavat mountains is a plateau on which Rudra resides. It is inhabited by Siddhas and Charanas. It is peopled with also many Pisachas (13:19). Amongst the Rakshasas and Pisachas some proceeded to the country of Uttara Kurus (15:33).
In Kurukshetra War
On Kaurava Side
Pisacha army took part in the Kurukshetra War under Bhagadatta the ruler of Pragjyotisha and other hilly tribes in the Himalayas:- Bhagadatta firmly resolved on fight, accompanied by the Magadhas, the Kalingas, and the Pisachas (6:88). Three thousand bowmen headed by Duryodhana, with a number of Sakas and Kamvojas and Valhikas and Yavanas and Paradas, and Kalingas and Tanganas and Amvashtas and Pisachas and Barbaras and Parvatas inflamed with rage and armed with stone, all rushed against Satyaki (7:118).
On Pandava Side
There were some Pisacha tribes on the side of Pandavas too.
Yudhishthira, with the Patachcharas, the Hunas, the Pauravakas and the Nishadas, became the two wings of the Pandava's millitary array, so also the Pisachas, with the Kundavishas, and the Mandakas, the Ladakas (Laddakh), the Tanganas, and the Uddras and the Saravas, the Tumbhumas, the Vatsas, and the Nakulas (6:50).