One of the main difficulties that the British faced in India during the 18th century was resistance from local rulers and the Indian population, who opposed British efforts to establish political and economic dominance over the region. The British also faced competition from other European powers, such as the French and Dutch, who were also interested in gaining control over Indian trade and territory. Additionally, the British had to contend with the challenging geography and climate of India, which made it difficult to establish and maintain their presence in the country.