When the British settled at Sydney Cove in 1788 the colonial government in Australia claimed all lands for the Crown from the formal declaration of annexation on 7 February 1788. The notion that Australia was terra nullius was used as justification for it being settled not invaded and that the Aboriginal population had no territorial rights over it. The first test of terra nullius in Australia occurred with the decision of R v Tommy indicating that the native inhabitants were only subject to English law where the incident concerned both natives and settlers and not where the case concerned only natives. The rationale was that Aboriginal tribal groups already operated under their own legal systems, a position supported by the decision in R v Ballard. Chief Justice Forbes stated that
I believe it has been the practice of the Courts of this country, since the Colony was settled, never to interfere with or enter into the quarrels that have taken place between or amongst the natives themselves. This I look to as matter of history, for I believe no instance is to be found on record in which the acts of conduct of the aborigines amongst themselves have been submitted to the consideration of our Courts of Justice. It has been the policy of the Judges, & I assume of the Government, in like manner with other Colonies, not to enter into or interfere with any cause of dispute or quarrel between the aboriginal natives. In all transactions between the British Settlers & the natives, the laws of the mother country have been carried into execution. Aggressions by British subjects, upon the natives, as well as those committed by the latter upon the former, have been punished by the laws of England where the execution of those laws have been found practicable. This has been found expedient for the mutual protection of both sorts of people; but I am not aware that British laws have been applied to the aboriginal natives in transactions solely between themselves, whether of contract, tort, or crime.
Although these judgements recognised the legal status of Aborigines as subject to English law but also to tribal law, they did not address directly the question of Aboriginal sovereignty with regard to the land. However, they did recognise that the Aborigines had a primitive form of legal system in relation to resolving disputes within and between tribal groups. This did not, however, void the principle of terra nullius.
In 1835, John Batman, one of the founding pioneers of Victoria, first settled at Port Phillip and made an attempt to buy the land from the Aboriginal people through a ‘treaty’. His treaty was signed on the banks of a creek on 16 June 1835 and was an agreement with eight Aboriginal leaders to transfer 100,000 acres of prime farming land in the Port Phillip area to Batman. However, this transaction was not as straightforward as it appears. Batman’s claim to this territory was based on the European idea of land ownership and legal contracts, a concept that was completely foreign to the indigenous people of Victoria. For them land was not about possession, but belonging. Territories may belong to different groups, but land cannot be bought or sold. Batman also claimed that he had negotiated with Aboriginal ‘chiefs’ who were in charge of this land. But he was actually negotiating with tribal elders who were not in a position to sell their people’s land, even if they had wanted to, and it is probable that none of the ‘signatories’ thought that this was what they were doing. The local Aborigines were as unable to comprehend the idea of selling their land as Batman was of appreciating the value it held for them. The exchange that took place that day, and the ‘treaty’ that marked it, was at best the result of a cultural misunderstanding by both sides. Inconsistencies in Batman’s accounts of how the ‘treaty’ was signed throw his claims of legitimate purchase into doubt. The story on the treaty deeds differs from the story in Batman’s journal and his report to Sir George Arthur, the VDL Governor. Historians now question whether the eight Aboriginal chiefs signed their ‘marks’ on the contract and Batman’s journal describes how he actually made the chiefs ‘signatures’ on the deeds himself.
Both the transfer to a person rather than the Crown and its implicit recognition of indigenous ownership and occupation of the land prompted Bourke to act. He effectively quashed the treaty with his Proclamation on 26 August 1835 and its republication on 3 May 1836 restating the doctrine of terra nullius upon which British settlement was based, reinforcing the notion that the land belonged to no one prior the British Crown taking possession of it in 1788.
Whereas, it has been represented to me, that divers of His Majesty’s Subjects have taken possession of vacant lands of the Crown, within the limits of this Colony, under the pretence of a treaty, bargain, or contract, for the purchase thereof, with the Aboriginal Natives; Now therefore, I, the Governor, in virtue and in exercise of the power and authority in me vested do hereby proclaim and notify to all His Majesty’s Subjects, and others whom it may concern, that every such treaty, bargain, and contract with the Aboriginal Natives, as aforesaid, for the possession, title, or claim to any lands lying and being within the limits of the Government of the Colony of New South Wales, as the same are laid down and defined by His Majesty’s Commission; that is to say extending from the Northern Cape, or extremity of the Coast called Cape York, in the latitude of ten degrees thirty seven minutes South, to the southern extremity of the said territory of New South Wales, or Wilson’s Promontory, in the latitude of thirty nine degrees twelve minutes South, and embracing all the country inland to the westward, as far as the one hundred and twenty ninth degree of east longitude, reckoning from the meridian of Greenwich, including all the islands adjacent, in the Pacific Ocean within the latitude aforesaid, and including also Norfolk Island, is void and of no effect against the rights of the Crown; and that all persons who shall be found in possession of any such Lands as aforesaid, without the license or authority of His Majesty’s Government, for such purpose first had and obtained, will be considered as trespassers, and liable to be dealt with in like manner as other intruders upon the vacant lands of the Crown within the said Colony. 
Its publication in the colony meant that people found in possession of land without the authority of the government would be considered trespassers. Although some contemporaries recognised that the Aboriginal occupants had rights in the lands, something confirmed in a House of Commons report on Aboriginal relations in 1837, the law followed and almost always applied the principles expressed in Bourke’s proclamation. Glenelg supported Bourke’s position completely rejecting the view that Aborigines had any rights to dispose of their land. Any recognition of Batman’s treaty would have had a catastrophic effect of Australian land policy and would have amounted to recognition that Australia was not the property of the Crown but of its indigenous population. It would have been an admission that since 1788 the British had been freely disposing of land that did not belong to them.
There is no reason to assume that the British government would not have entered into treaty arrangements with the Aboriginal people as it did in New Zealand and elsewhere had it recognised their ‘ownership’ of the land. William Blackstone, who was regarded as authoritative on the matter in subsequent cases in several countries with legal systems based on English common law, drew a clear distinction between colonies won by conquest or treaty and those where ‘lands are claimed by right of occupancy only, by finding them desert and uncultivated (though he was unclear on whether they were uninhabited), and peopling them from the mother countries. This ambiguity enabled later commentators to argue that only cultivated land was in actual possession and that in colonies of settlement English law was ‘immediately there in force’ on the assumption that no prior legal code and no land tenure had ever existed’: in other words it was terra nullius. The words of the Privy Council in Vajesingji v Secretary of State for India in 1924 are among many other pronouncements that defined the concept of terra nullius unambiguously: ‘territory hitherto not occupied by a recognised ruler’. New Holland was considered a paradigm case of terra nullius because the British could identify no territorial units with a recognisable form of government, not because there had been no Aboriginal inhabitants. It is the High Court that was mistaken in believing that British explorers, Whitehall officials or Australian colonists held the false belief that Australia was uninhabited or nearly so. The consistent legal doctrine from 1788 was that the original British claim of sovereignty extinguished all prior rights to property and that after 1788 ‘all titles, rights, and interests whatever in land which existed’ were the ‘direct consequence of some grant from the Crown’. This would not change until the Australian High Court’s decision in the Mabo Case in 1992.
 The principle of British sovereignty over Australia was asserted on four occasions: in 1788, 1824, 1829 and 1879.
 See Reynolds, Henry, Aboriginal sovereignty: reflections on race, state, and nation, (Allen & Unwin), 1996, pp. 1-15, 86-107 and especially Attwood, Bain, Possession: Batman’s Treaty and the Matter of History, (Melbourne University Press), 2009.
 Monitor, 28 November 1827.
 Sydney Gazette, 23 April 1829.
 Brown, P.L., ‘Batman, John (1801-1839)’, ADB, Vol. 1, pp. 67-71. See also, Bonwick, John, John Batman, the founder of Victoria, (Fergusson and Moore), 1868, pp. 66-83.
 Public Record Office: PRO: CO 201/247 ff 411 r + v. It was published in the New South Wales Government Gazette, 2 September 1835.
 In practice, although Bourke’s action had voided any ‘treaty’ that was made, it did not prevent significant movement of settlers of the Port Phillip Association from VDL and from other parts of NSW into the Port Phillip District from late 1835 onwards. In his despatch of 10 October 1835, Bourke recommended that the settlement should be recognised and, though initially the Colonial Office had doubts about doing so, Lord Glenelg supported Bourke’s recommendations and on 9 September 1836 a notice recognised the existence of a settlement that had already existed for a year.
 Report from the Select Committee on Aborigines (British Settlements): with the minutes of evidence, appendix and index, 1837, pp. 10-15
 Prest, W., ‘Law for Historians: William Blackstone on women, colonies and slaves’, Legal History, Vol. 11, (2007), pp. 105-115, especially pp. 109-111.
 Law Report, 51 Ind. App. (1924) at 360, cit, Dawson J. in 107 Australian Law Report, 1, p. 94.
 The Mabo case radically altered this position and increasingly historians view Australian colonisation as ‘conquest’ rather than ‘settlement’. Stephenson M.A. and Ratnapala, Suri, (ed.), Mabo: A Judicial Revolution, The Aboriginal Land Rights Decision and its impact on Australian Law, (University of Queensland Press), 1993.