This fort is testament to the eternal willpower of the Rajputs and their obsessive belief in the divine destiny.
Rawal Devaraj, the Bhati emperor, lost his family and kingdom to a treacherous enemy attack when he was a young child aged around 10. Then on he took it upon himself to recreate the empire of his ancestors all by himself from ground up, more than 1000 years ago.
On the bank of now-dried Saraswati river, he founded the fortress of Dera Rawal, now called Derawar. He ruled for many decades and recreated an empire more glorious than it had ever been, conquering much of Sindh, Western-Rajasthan and Punjab uniting the Western Indo-Aryans under one flag.
Legacy of his rule is, Bhati became the dominant Rajput tribe in Punjab, Multan, Sindh, and Western Rajasthan.
The fort remain in the hands of the imperial Bhati family until the mid 1700s. By mid 1700s imperial family based around what is now Jaisalmer was surrounded by enemies from all directions. Talpur Baluchs supported by the Persian Empire were taking their possessions in Sindh, Rathores were advancing in Barmer, Pokharan, and even parts of north Jaisalmer!
Using the chaos of 1700s, the once shepherd Kalhoro tribe magically claimed they are now Abassis. Supported by the rulers of Multan, they created a large rag-tag militia of peasant kharijites from Multan. The 1:50 outnumbered rajput forces put up against these kharijites for decades, ultimately losing Southern and western Multan to them. Kalhoros based themselves in Bahawalpur and named it 'Baghdad al Jadid'. The reason for the defeat was simple, most of the Bhati forces were destroyed in battle against the Rathores and Talpurs, making Derawar an easy target for Bahawalpur forces.
The lesson we have to take from this is, inter-Rajput wars weakened all of us. Had Jodhpur focused on Gujarat instead of attacking Jaisalmer, Sindh, Gujarat, and Punjab would still be in Rajput hands.