The assumption of direct administration of India by the Crown following the Great Revolt of 1857, necessitated the creation of what came to be called Indian Civil Services (ICS). The competition for entry into the ICS was open to all natural-born subjects of Her Majesty, whether European or India. The maximum age for admission was at first 23, lowered in 1859 to 22, and teh selected candidates were to remain on probation in England for a year.
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In 1870 an Act was passed authorizing the appointment of Indians to the higher offices without any examination, but the effect to this legislation was given only in 1879. The rules provided that “a proportion not exceeding one-sixth of the total covenanted Civil Servants in any year should be natives selected in India”. The British later introduced simultaneous examinations in both India and England. After Independence ICS was renamed as IAS ( Indian Administrative Service).