The Gurkhas became the most trusted soldiers because

The recruitment of the Company's army in the eighteenth century was not just building on the existing traditions of the North Indian military labour market; those traditions were being adapted to British imperial preferences. The recruitment system endorsed the traditional British preference for peasants as the best potential recruits and the stereotype that wheat-eating groups were physically suitable. During the formative phase, Warren Hastings did not want to disturb the existing caste rules in the affairs of the army. So the Company's army consisted mainly of upper-caste Brahman and Rajput landed peasants and the Bhumihar Brahman peasants from north and south Bihar, both wheat-eating regions. These people joined because the pay, allowances, pension and resettlement provisions of the Company exceeded those of the regional states, and salaries were paid regularly. The deliberate policy of respecting the caste, dietary, travel and religious practices of the sepoys fostered a high-caste identity in the army. Cornwallis, despite his preference for Anglicisation, did not disturb this organization, and so the Company came to possess a high-caste army that was prone to revolt when its privileges were cut from the 1820s. As the Company's territories expanded, recruitment was also tried among the hill tribes; in the hills payment was offered through the Mughal system of ghatwali service tenures. The defeat of Mysore and the Marathas created a vast reservoir of disbanded soldiers, but the Company's army could not absorb all of them, as it did not want too large an Indian force. From 1815 there was an experiment to recruit Gurkha soldiers from among the Nepalis, Garhwalis and Sirmouli hill men. A skilful blending of the Nepali martial tradition with European training and discipline made the Gurkhas the most trusted soldiers in the British army.