Indians had increasingly been demanding a greater role in the government of their country since the late 19th century. The Indian contribution to the British war effort during the First World War meant that even the more conservative elements in the British political establishment felt the necessity of constitutional change, resulting in the Government of India Act 1919. That Act introduced a novel system of government known as provincial "diarchy", i.e., certain areas of government (such as education) were placed in the hands of ministers responsible to the provincial legislature, while others (such as public order and finance) were retained in the hands of officials responsible to the British-appointed provincial Governor. While the Act was a reflection of the demand for a greater role in government by Indians, it was also very much a reflection of British fears about what that role might mean in practice for India (and of course for British interests there).