Several scholars and historians have attested the Telugu origin of Vijayanagar empire. The famous British traveler Francis Buchanan while on a visit to Beidur in Mysore (Karnataka) in 1801, was shown by one Ramappa Varmika a Sanskrit book in his possession called the Vidyaranya Sikka, which mentioned that the founders of Vijayanagar were Harihara and Bukka, guards of the treasury of the Kakatiya King Prataparudra of Warangal . These young brothers met a spiritual teacher, Vidyaranya, the sage of Sringeri monastery, who guided them to establish the kingdom of Vijayanagar to safeguard Hindu religion. This was in 1336 and Harihara was made first king of the fledgling empire. Robert Sewell considered various such theories and concluded that Harihara and Bukka were treasury officers of Golla/Kuruba caste, in the court of Warangal (Kakatiya dynasty). The Delhi sultan who captured and converted the brothers to Islam, sent them back to put down the rebellion of Hoysala king. They succeeded in suppressing the rebellion but laid foundation of an independent kingdom at the behest of Vidyaranya.
Well known historians of South India also supported the conclusions of Sewell based on extensive research and information provided by the Sanskrit and Kannada treatises such as Vidyaranya Kalajnana (in Sanskrit), Vidyaranya Vrittanta, Rajakalanirnaya, Piramahasamhiti and Sivatatva Ratnakara (all in Kannada). A reputed scholar from Karnataka described seven traditional accounts of the origin of Harihara and Bukka, out of which five inclined towards their Telugu origin. Well-known historian, Saletore surmised that Hampi was lying outside the Hoysala territory and supported the Telugu origin of Vijayanagara kings. The Telugu Golla identity of Harihara and Bukka and that they worshipped the goddess Bhuvaneswari was also established. Indirect evidences such as the employment of predominantly Telugu Nayaks (Kamma, Balija, Velama and Reddy) for revenue collection throughout the empire also supported the Telugu affinity.
Muslim historians and scholars of the time such as Ziauddin Barani, Isarni and Ferishta and foreign visitors like Ibn Batuta and Nuniz also recorded that the brothers were serving the King Prataparudra and were made captive after the fall of Warangal . According to another historian who based his research on evidence culled from inscriptions such as Gozalavidu record, "the founders of Vijayanagara were at first in the service of the last Kakatiya king Prataparudra of Warangal, and that when that monarch was defeated by Muhammad bin Tughluq and taken prisoner, they fled to Kampili and took refuge in the court of Kampilideva” . On the outbreak of a rebellion in Kampili the brothers were sent by Tughlaq with an army to Kampili to reconquer it from the rebels and rule the province as his deputies. They successfully accomplished the task but under the influence of Vidyaranya they renounced Islam, and threw in their lot with the Andhra nationalists led by Musunuri Nayaks who had just then succeeded, under the leadership of Kaapaya, in expelling the Muslims and re-establish the national independence. Harihara and Bukka then reverted to their ancient faith and having declared independence, assumed the leadership of the Hindus of Kampili in their fight against the Muslims.
Kaapaya and Bukka actively collaborated with each other to ward off the Muslim threat, probably because of their close association in the court of Warangal. Historians surmised that the establishment of Vijayanagar kingdom drew inspiration from the successful exploits of Kaapaya. After the demise of Kaapaya Nayaka, Reddys of Kondavidu and Velamas of Rachakonda asserted their independence thus bringing them into a natural conflict with Vijayanagar kings whose sole aim was to consolidate Hindu opposition to alien dharma. Velamas colluded with Bahmanis to save their territories thus making them enemies of Vijayanagar. It was Krishna Deva Raya who vanquished Reddys and Velamas and unified the South.
Recent epigraphal research and interpretation of inscriptions not known to earlier historians support the theory that the founders of the empire were local princes under the service of the Hoysala kings. Inscriptions prove that Harihara I and Bukka Raya I were in the Hoysala service a decade before their arrival at Kampili (in modern Bellary district). Not only did the widow of Hoysala Veera Ballala III participate in the coronation of Harihara I in 1346, her name appears before that of the Vijayanagara King Harihara I in a 1349 inscription indicating he gained legitimacy for being a devoted heir of the Hoysalas. Further, it is proven that the original founding of Vijayanagara was in 1320 by Veera Ballala III, then known as Vijayavirupaksha Hosapattana. By 1344, the transfer of power from the Hoysala Empire to the emerging Vijayanagara empire seems to have been gradual and without bloodshed, as ex-Hoysala officers melted away from a crumbling Hoysala power now to support the Sangama cause. In 1346, Harihara I made a grant to Bharati Tirtha in the presence of Krishnayitayi, queen of Hoysala Veera Ballala III, who herself made a grant on the same day. Harihara I was a commander in the Hoysala Kingdom and had been appointed by Veera Ballala III with autonomous powers after the fall of the Seuna and Kampili kingdoms, to administer the northern territories. The very first fortress Harihara I built was the fort at Barakuru in coastal Karnataka in 1336, when he was a Hoysala commander in charge of its northern territories from his seat in Gutti, modern Ananthapur district in Andhra Pradesh, at that time a Hoysala territory. He assumed the Kannada titles Purvapaschima Samudradhishvara (Master of eastern and western and occeans), Arirayavibhada (fire to the enemy kings) and Bhashegetappuvarayaraganda (punisher of the ruler who failed to keep a promise). When Veera Ballala III died fighting the Sultan of Madurai, Harihara I seems to have gained soveriegn powers over the entire Hoysala territory.
It has been pointed out that even famous Telugu scholars Vallabharaya and Srinatha, in their works called the Sangama brothers Karnata Kshitinatha, indicating they were a Kannada family. An early inscription of Harihara II called him , Lion to the scent elephant of the Andhra king, demonstrating their anti-Telugu propensity. Persian author Ferishta of Vijayanagara days wrote the emperors as "Roies of Karnataka". The Kannada writings of that time Chikkadevaraya Vamshavali and Keladinripa Vijayam state that the Sangama brothers were Kuruba by caste making them people of Karnataka Regarding the earliest modern work on Vijayanagara Empire by Robert Sewell, A Forgotten Empire, 1901, it is claimed that he had not used all sources but had copiously used travellogues and other works by only European travellers.
Almost half of the Vijayanagar inscriptions are in Kannada out of a total of about 7000 available today and use surnames which are pure Kannada titles such as Bhashegetappuva - rayara - ganda, Moorurayaraganda and Arirayadatta. The remaining inscriptions are in Sanskrit, Telugu and Tamil. The Karnataka Empire or Vijayanagar Empire was originally of the Karnataka region and it drew its inspirations from the Hoysala Empire and the Western Ganga Dynasty of the Karnataka and the Chola and Pandya of the Tamil country. Inscriptional evidence shows that Ballappa Dandanayaka, a nephew of Hoysala Veera Ballala III was married to a daughter of Harihara I, the founder of the empire. This is claimed proof enough of the association Sangama brothers had with the Hoysala family.
It is also asserted that the theory of capture of Harihara I and Bukka Raya I by the Sultan of Delhi and conversion to Islam is false and that the testimony of epigraphs proves that the area around Hampi constituted their homeland. The empire never had a Telugu origin. The patron saint of the early kings was saint Vidyaranya, the 12th Shankaracharya of Sringeri in Karnataka and this is proof enough of their unquestionable identity with the Kannada country. About the Muslim records that claim a Telugu origin of Harihara I and Bukka Raya, it is said that they are neither unanimous nor reliable in their claims. In those days of religious rigidity, it is too far fetched to accept a theory of conversion to Islam and reconversion to Hinduism and still manage to win the trust and loyalty of Hindu subjects, in an hour of impending invasions. It is further pointed out the great devotion the founders of the empire had in Lord Chennakeshava of Belur and Lord Virupaksha of Hampi testifying to their origin from Kannada country, though in political and administrative matters, the Vijayanagar kings followed the Hoysala, Kakatiya, Chola framework in the various regions of the empire. It is also claimed that the Sangama brothers even signed their Sanskrit records in Kannada as Srivirupaksha and used their Kannada titles even in Telugu, Tamil and Sanskrit records. No such Telugu titles were used by them. The popular chieftain and patriot of those times, prince Kumara Rama of Kummatadurga or simply Kummata (Kampili kingdom in Bellary District) may have been related to Sangama, father of Harihar I. This evidence exists in literary works by Nanjunda (Kumara Rama Charita) and others that the early Vijayanagar kings raised memorials at Sandur, Chitradurga and Dharwad to sing the glory of Kumara Rama's valor and show their continued efforts to build an empire in his legacy. All this proves the matrimonial relations the Sangama family had with the Kummata family.