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Secret Instructions

James Cook’s famous Endeavour voyage was originally commissioned by the Royal Society of London as a scientific mission. When the Admiralty (Royal Navy) became aware that the Society was planning to commission a sea journey to the Southern Hemisphere to collect scientific data, its members saw an opportunity to become involved. However, their motivations were very different to those of the Royal Society.

The Admiralty’s interest lay in preserving and increasing the power and prestige of the British Crown. The discovery of new and efficient routes of navigation and commercial trading opportunities would increase the advantages held by Britain as a maritime power. A journey such as that proposed by the Royal Society would provide great opportunities to achieve this aim. The Royal Society and Admiralty agreed on a joint venture in which the latter’s territorial ambitions could be concealed behind the more benign exploratory goal of expanding knowledge of the world.

On 30 July 1768, the Lords of the Admiralty signed Cook’s instructions for the Endeavour voyage, and they were classified as secret. The instructions were in two parts, the second of which was sealed, to be opened only by Cook. The first task was to sail to Tahiti from where Cook and his crew were instructed to observe the transit of Venus. The document includes the request that:

When this service is perform’d you are to put to Sea without Loss of Time, and carry into execution the Additional Instructions contained in the inclosed Sealed Packet.

The sealed instructions held the Admiralty’s reasons for supporting the voyage: in addition to observing the transit of Venus, Cook was commanded to find the Great South Land, a ‘Land of great extent’ that was thought to exist in southern latitudes:

You are to proceed to the Southward in order to make discovery of the Continent above-mentioned until you arrive in the latitude of 40º, unless you sooner fall in with it.

The second page instructs Cook ‘with the Consent of the Natives to take possession of Convenient Situations in the Country in the Name of the King of Great Britain’. With these directives, Cook was authorised to place any Indigenous inhabitants of the Great South Land under the rule of the King of England.

On reaching the coordinates set out by the Admiralty and deeming to have not ‘discovered’ the Great South Land, Cook looked to the Admiralty’s instructions for direction:

“…if you shall fail of discovering the Continent beforemention’d [the Great South Land], you will with upon falling in with New Zeland carefully observe the Latitude and Longitude in which that Land is situated and explore as much of the Coast as the Condition of the Bark, the health of her Crew, and the State of your Provisions will admit of having always great Attention to reserve as much of the latter as will enable you to reach some known Port where you may procure a Sufficiency to carry You to England either round the Cape of Good Hope, or Cape Horn as from Circumstances you may judge the Most Eligible way of returning home.”

Dutifully, Cook sailed west and eventually fell upon the coast of New Zealand. He stayed in New Zealand waters from late 1769 through until around April 1770. He undertook extensive mapping and observations which established New Zealand was comprised of two principal islands and was separate from any Great Southern Land.

Following his directive to return to England, Cook sailed westward, opting to return by way of Batavia and the Cape of Good Hope.

Before closing, the Admiralty’s letter issued a final catch all directive to Cook:

“You will also observe with accuracy the Situation of such Islands as you may discover in the Course of your Voyage that have not hitherto been discover’d by any Europeans and take Possession for His Majesty and make Surveys and Draughts of such of them as may appear to be of Consequence, without Suffering yourself however to be thereby diverted from the Object which you are always to have in View, the Discovery of the Southern Continent so often Mentioned.”

Sailing west from New Zealand, Cook reached the southern coast of New South Wales on 20 April 1770, and sighted land at what we now know as Point Hicks, in Victoria. Heading north, Cook landed at Botany Bay one week later, before continuing north to the tip of Queensland. There, on Possession Island, just before sunset on Wednesday 22 August 1770, Cook declared the continent a British possession.

Cook followed his orders zealously to observe any lands he came across. While sailing along the east coast, Cook and his crew made many forays into the hinterland, collecting samples of flora and fauna, and, on a number of occasions interacting with the local people. His observations and surveys along the New South Wales coastline on his first voyage formed the basis for Britain’s decision to establish a colony at Botany Bay. His meticulous charting of the coast contributed to the Admiralty’s charts of Australian waters that were prepared 20 years after his voyage along the eastern coast.


  1. The Admiralty instructed Cook to take possession of the Great South Land, "with the Consent of the Natives". Discuss the concept of consent in this context of pre-contact Indigenous societies. Had Cook discovered the fabled South Land and had he met with it’s inhabitants, do you think it would have been possible for Cook to have obtained such consent?
  2. The Admiralty's directive to Cook regarding the Great South Land instructed him to take possession of the land with the consent of the local inhabitants, but the later instruction to "observe with accuracy….and take possession for His Majesty” of any other land "not discovered by Europeans" does not mention consent of the local people. What reasons could be behind this difference in approach/wording?
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