(Prepared by Prakash Chaudhari)
Anjanas are the descendant of king Puru (Porus) who inhabited in the regions of Shahpur and Sarghoda on the bank of Chenab River, the modern-day Pakistan. They were further divided into 2 branches, 1) Chaudhan tribe (aka chahamanas) of Shahpur 2) Paramara tribe of Sarghoda. Both Chaudhan and Paramaras tribe were mainly occupied in farming and raising livestock on the fertile land of Chenab basin.
During that era, Muslim invasions recurrently started en route through their native regions. Due to the conflicts with Muslim invaders, some groups from both the tribes migrated with their farm livestock, horses and arsenals towards southeast direction of Indian subcontinent and settled down at uninhabited area in and around Gadaraghatta (aka Mount Abu). Hills of Gadaraghatta protected them from the eyes of the adversaries. They established themselves along with their livestock in a safe and secure mode. They believed that their protection against enemies is the blessing of Goddess Arbuda situated at the top hill of mountain and therefore they accepted Goddess Arbuda as their own deity.
Their rituals had evolved amongst them. Chaudhans and Paramaras started marriages from each other tribes. Chaudhans were later known as Chaudhari and relocated to Naddula and Jalor region. Paramaras kept their gotra names as their last names and settled at the same location, Arbuda (Gadaraghatta) region. Later, since last 2 centuries, they adopted their last names as Patel.
Migration to North Gujarat:
Anhilwara Patan was capital of the Chalukya (also known as the Solankis) who ousted the Chapotkatas. According to American historian Tertius Chandler, the ancient bastion was the tenth-largest city in the world in the year 1000, with a population of approximately 100,000.
Mularaja-II had ascended the throne as a boy after the demise of his father Ajayapala. However, it was actually his mother Naiki Devi, the daughter of the Kadamba king of Goa, who took over the reins of the kingdom.
Muhammad Ghori deployed massive hordes of army to invade prosperous and fortified Anhilwara Patan knowing that the boy king and his mother couldn’t defend the kingdom against his mighty force. Naiki Devi found out the Ghori’s progression to invade her kingdom from informants. Undaunted by the prospect of Ghori’s imminent attack, she took command of the Chalukyan force and threw herself into organizing a well-planned opposition to the invading army. She sent out emissaries to forge crucial alliances and requested support from nearby provinces, including Prithviraj Chauhan. While these kingdoms did not accede to her request, she did receive assistance from Chalukyan feudatories such as the leaders of the Naddula Chahamana clan, the Jalor Chahamana clan, and the Arbuda Paramara clan who were very well familiar with the rugged terrain at the foothill of Gadaraghatta aka Mount Abu. The narrow hill passes of Gadaraghatta were unfamiliar ground for Ghori’s invading army. Chahamanas Anjanas and Paramara Anjanas fought fierce guerrilla war from the foothills of Gadaraghatta (Mount Abu) along with Naiki Devi’s army and crushed the invading force. After facing the major defeat, Ghori retreated, fled away from foothills and never thought of invading Anhilwara again.
The prudent queen recognized an abundant valor of Anjanas (Chahamanas and Paramaras). She presented some of them very large plantations to settle down in the plain region of North Gujarat in her kingdom to buffer the routes of invaders. This is how Anjanas became the settlers of North Gujarat.
 History of Anhilwar Patan
Note: The theory presented above is from the ancient history of Indian subcontinent and therefore it is likely to be correct as opposed to some prevailing epic stories and myth of Anjana origins.