The interest of the British Government of India in Afghanistan during the 19th century was primarily driven by the aim to prevent the Russian empire from gaining influence over Afghanistan. This was important to the British because they wanted to safeguard their control over neighboring territories and protect their own interests in the region. If Russia had gained a foothold in Afghanistan, it could have posed a threat to British control in India, which was a crucial part of the British Empire at the time. Therefore, the British government saw it as necessary to maintain a friendly government in Afghanistan that would not align with Russian interests. This strategic concern was the main motivation behind the British interest in Afghanistan during this period.