With the large revenue earned from these jagirs, he built the Chintamani Durg (Junagarh fort) on a plain which has an average elevation of 760 feet (230 m). He was given the jagirs (lands) of Gujarat and Burhanpur. Rai Singh's successful military exploits, which involved winning half of Mewar kingdom for the Empire, won him accolades and rewards from the Mughal emperors. During the Mughal Empire's rule in the country, Raja Rai Singh accepted the suzerainty of the Mughals and held a high rank as an army general at the court of the Emperor Akbar and his son the Emperor Jahangir. Īround a century after Rao Bika founded Bikaner, the state's fortunes flourished under the sixth Raja, Rai Singhji, who ruled from 1571 to 1611. Bika built a fort in 1478, which is now in ruins, and a hundred years later a new fort was built about 1.5 km from the city centre, known as the Junagarh Fort. Bika's name was attached to the city he built and to the state of Bikaner ("the settlement of Bika") that he established. Though it was in the Thar Desert, Bikaner was considered an oasis on the trade route between Central Asia and the Gujarat coast as it had adequate spring water. He therefore decided to build his own kingdom in what is now the state of Bikaner in the area of Jangladesh.
As the first son of Jodha he wanted to have his own kingdom, not inheriting Jodhpur from his father or the title of Maharaja. He was the first son of Maharaja Rao Jodha of the Rathore clan, the founder of Jodhpur and conquered the largely arid country in the north of Rajasthan. Later,Rao Bika a Rajput established the city of Bikaner in 1488.A treaty between Nera and Bika gives the name Bikaner Prior to the mid 15th century, the region that is now Bikaner was a barren wilderness called Jangladesh.