He was the son of Kama and ascended the throne in 1094 A.D. As his age was very less at the time of his accession, his mother Mayanalladevi looked after administration for some time.
War with Chabamanas of Naddul: When Jaya Singh Siddharaja was only a child, Chahamana king Jojjala attacked his capital Anhilwad and brought it under his control. But later on Jaya Singh Siddharaja again conquered Anhilwad.
War with Parmaras: Both ashrama and Jaya Singh Siddharaja jointly attacked Parmara king Naravarman. A terrible war was fought for 12 years and therefore Naravarman was made prisoner but somehow became free after some time. After Naravarman`s death his son Yasovarman also fought against Jaya Singh, but he was also defeated and made a prisoner. Jaya Singh Siddharaja thus established his authority over the entire Malva and adopted the title of Avantinath. However, inscriptions indicate that he could not maintain his authority over Malva for a long time and Yasovarman again conquered it.
War with Chandellas: Jaya Singh Siddharaja had defeated Chandella king Madanvarman and established has authority over Bhilsa.
War with Amirs of Saurashtra: Jaya Singh Siddharaja attacked the Amirs of Saurashtra and after making their king Navadhan as prisoner he eventually incorporated his entire kingdom into his empire.
War with the Chalukyas of Kalyani: Jaya Singh Siddharaja had also defeated king Vikramaditya of Chalukya dynasty.
War with the Chahamanas of Shakair Bhari: A terrible war was fought between Chahamana king Arnviraja and Jaya singh Siddharaja in which Arnoraja was defeated. However, later on Jaya Singh Siddharaja married his daughter with him and returned his kingdom.
Estimate: Jaya Singh is ranked among the important Chalukya kings. His empire extended to Jaipur, Jodhpur and from Bhilsa to Kthiawar. Besides being great conqueror he was also a lover of education and literature. A famous Jain scholar, Hemchandra was placed in his court with all his dignity an pride. He opened many educational institutions where law, astrology and other subjects were taught. He was a follower of Shaiva religion and built many temples of Siva as well.