Prithviraj was born to the Chahamana king Someshvara and queen Karpuradevi (a Kalachuri princess).[7] Both Prithviraj and his younger brother Hariraja were born in Gujarat, where their father Someshvara was brought up at the Chaulukya court by his maternal relatives.[7] According to Prithviraja Vijaya, Prithviraj was born on the 12th day of the Jyeshtha month. The text does not mention the year of his birth, but provides some of the astrological planetary positions at the time of his birth, calling them auspicious. Based on these positions and assuming certain other planetary positions, Dasharatha Sharma calculated the year of Prithviraj's birth as 1166 CE (1223 VS).[8][9]
The medieval biographies of Prithviraj suggest that he was educated well. The Prithviraja Vijaya states that he mastered 6 languages; the Prithviraj Raso claims that he learned 14 languages, which appears to be an exaggeration. The Raso goes on to claim that he became well-versed in a number of subjects, including history, mathematics, medicine, military, painting, philosophy (mimamsa), and theology. Both the texts state that he was particularly proficient in archery.
Early in his career, Prithviraj achieved military successes against several neighbouring Hindu kingdoms, most notably against the Chandela king Paramardi. He also repulsed the early invasions by Muhammad of Ghor, a ruler of the Muslim Ghurid dynasty. However, in 1192 CE, the Ghurids defeated Prithviraj at the Second battle of Tarain, and executed him shortly after. His defeat at Tarain is seen as a landmark event in the Islamic conquest of India, and has been described in several semi-legendary accounts. The most popular of these accounts is Prithviraj Raso, which presents him as a Rajput.
The extant inscriptions from Prithviraj's reign are few in number and were not issued by the king himself.[1] Much of the information about him comes from the medieval legendary chronicles. Besides the Muslim accounts of Battles of Tarain, he has been mentioned in several medieval kavyas (epic poems) by Hindu and Jain authors. These include Prithviraja Vijaya, Hammira Mahakavya and Prithviraj Raso. These texts contain eulogistic descriptions, and are, therefore, not entirely reliable.[2] Prithviraja Vijaya is the only surviving literary text from the reign of Prithviraj.[3] Prithviraj Raso, which popularized Prithviraj as a great king, is purported to be written by his court poet Chand Bardai. However, it contains many exaggerated accounts, much of which is not useful for the purposes of history.[2]
Other chronicles and texts that mention Prithviraj include Prabandha-Chintamani, Prabandha Kosha and Prithviraja Prabandha. These were composed centuries after his death, and contain exaggerations and anachronistic anecdotes.[2] Prithviraj has also been mentioned in Kharatara-Gachchha-Pattavali, a Sanskrit text containing biographies of the Kharatara Jain monks. While the work was completed in 1336 CE, the part that mentions Prithviraj was written around 1250 CE.[4] The Alha-Khanda (or Alha Raso) of the Chandela poet Jaganika also provides an exaggerated account of Prithviraj's war against the Chandelas.[5]
Some other Indian texts also mention Prithviraj but do not provide much information of historical value. For example, the Sanskrit poem anthology Sharngadhara-paddhati (1363) contains a verse praising him, and the Kanhadade Prabandha (1455) mentions him as an earlier incarnation of the Jalore Chahamana king Viramade.
Prithviraj moved from Gujarat to Ajmer, when his father Someshvara was crowned the Chahamana king after the death of Prithviraja II.[11] Someshvara died in 1177 CE (1234 VS), when Prithviraj was around 11 years old. The last inscription from Someshvara's reign and the first inscription from Prithviraj's reign are both dated to this year. Prithviraj, who was a minor at the time, ascended the throne with his mother as the regent.[8] The Hammira Mahakavya claims that Someshvara himself installed Prithviraj on the throne, and then retired to the forest. However, this is doubtful.[12]
During his early years as the king, Prithviraj's mother managed the administration, assisted by a regency council.[12]
Kadambavasa served as the chief minister of the kingdom during this period. He is also known as Kaimasa, Kaimash or Kaimbasa in the folk legends, which describe him as an able administrator and soldier devoted to the young king.[8] Prithviraja Vijaya states that he was responsible for all the military victories during the early years of Prithviraj's reign. According to two different legends, Kadambavasa was later killed by Prithviraj. The Prithviraja-Raso claims that Prithviraj killed the minister after finding him in the apartment of the king's favourite concubine Karnati. Prithviraja-Prabandha claims that a man named Pratapa-Simha conspired against the minister, and convinced Prithviraj that the minister was responsible for the repeated Muslim invasions. Both these claims appear to be historically inaccurate, as the much more historically reliable Prithviraja Vijaya does not mention any such incident.[13]
Bhuvanaikamalla, the paternal uncle of Prithviraj's mother, was another important minister during this time.[13] According to Prithviraja Vijaya, he was a valiant general who served Prithviraj as Garuda serves Vishnu.[14] The text also states that he was "proficient in the art of subduing nāgas". According to the 15th-century historian Jonaraja, "naga" here refers to elephants. However, Har Bilas Sarda interpreted Naga as the name of a tribe, and theorized that Bhuvanaikamalla defeated this tribe.[13]
According to historian Dasharatha Sharma, Prithviraj assumed actual control of the administration in 1180 CE (1237 VS)