Leonard Casley declared the Principality an independent province in 1970 in response to a dispute with the government of Western Australia over what the Casley family considered draconian wheat production quotas. 52 million in the hope the claim would force a revision of the quota. Casley also claims he made a successful Court claim using the law of unjust enrichment to successfully seize government land surrounding his farm which he hoped would increase his wheat quota. Two weeks later, Casley claims the government introduced a bill into Parliament to “resume” his and the other families’ lands under compulsory acquisition laws. At about this time, Casley claims that in correspondence with the Governor-General’s office, Casley was on one occasion inadvertently addressed as the “Administrator of the Hutt River Province”. Casley claims this constitutes legally binding recognition of the Principality.
At about this time, Casley styled himself “His Majesty Prince Leonard I of Hutt”. Casley did this because he believed it would enable him to take advantage of the British Treason Act 1495, which provides that the de facto king of a nation cannot be guilty of treason in relation to any act against the lawful king and that anyone who interfered with that monarch’s duties could be charged with treason. Casley says he continued to sell his wheat in open defiance of the quota. Casley believes that under Australian law the federal government had two years to respond to Casley’s declaration of sovereignty. On 2 December 1977, famously, the Principality declared war on Australia. Casley notified authorities of the cessation of hostilities several days later. It may be more than coincidence that this declaration of war came in just a few months after a court decision where Casley was fined for failing to furnish the ATO with certain documents.
In 1978, Casley appealed to the Supreme Court of Western Australia against a conviction for conducting a shop on his property without a permit. His appeal was dismissed, except to alter the penalty. Casley did not suggest his land was not subject to Australian law in this appeal. In 1970 and 1984, Casley unsuccessfully defended civil legal actions brought against him by private parties – in the former case, an injunction was granted against him in relation to a land deal, and in the latter case, he was ordered to pay debts owed to a publishing company he had contracted to print copies of a book called The Man, which was about himself and his achievements.
In the early 1980s, the Principality declared itself to be a kingdom, but soon reverted to its original status of a principality. The Principality released a number of stamps and coins. In about 2006, Casley was again successfully prosecuted by the ATO. He sought special leave to appeal to the High Court of Australia, but his application was dismissed with the comment that his arguments were “fatuous, frivolous and vexatious”. In September 2006, Prince Leonard decided to change the Province’s name to “Principality of Hutt River”.