Chief Secretary was the title of a senior civil servant in various colonies of the British Empire. Prior to the dissolution of the colonies, the Chief Secretary was the second most important official in a colony of the British Empire after the Governor, typically termed the Colonial Secretary and often an office held by the Premier or a similar politically elected minister, and with a portfolio which were equivalent to what was later termed the Home Secretary's office.
Originally the secretary to the Governor as well as secretary of the Colony this office was at first known as the Colonial Secretary or Principal Secretary outside British North America where the equivalent title was Provincial Secretary. In 1821, Governor of New South Wales Philip Gidley King wrote that the Colonial Secretary:
In Ireland, the role of Chief Secretary dated from 1660.
The Colonial Secretary in the Colony of New South Wales and most of the other Australian colonies during the nineteenth century was a political position and not the position of a civil servant. The Colonial Secretary was thus a government minister and politician and the position was fundamentally equivalent to the later term 'Home Secretary' and it was commonly (but not always) held by the Colonial Prime Minister, later referred to as Premier. The function of Colonial Secretary and secretary to the Governor were thus separated in 1824 and several Australian colonies renamed their 'Colonial Secretary' as 'Home Secretary' during the 1890s and just before separation.
After the grant of responsible government, this office like its British equivalent, the First Lord of the Treasury was frequently the formal position held by the Colonial Premier because the office of Premier was not mentioned in any legislation. The Cape Colony was unusual in giving the Colonial Secretary at the Cape responsibility for defence. Several of the Australian states and territories retained the title for many decades, the Chief Secretary's Departments ultimately evolving into the modern Premier's Departments in those states, although the Chief Secretary position itself became separate from that of the Premier, and evolved differently in different jurisdictions: in some places it became the equivalent of the British Home Secretary or a Minister of the Interior elsewhere. New Zealand abolished the office in 1907.