The Republic of Western Australia
Following the Territorial gains in the Great Lakes War [OTL war of 1812], the British put in a lot more effort into settling their North American Colonies. But what is added to one, must be removed from another. Settler colonies like Uganda and Kenya were never pursued and what few settler colonies were established were lessened. This is most evident in the Republic of Western Australia. The Colony had less settlers arrive from the East and in turn, developed its own culture. During federation, Western Australia voted no, leading to a divided Australia. In the early 1910's, the Colony of Western Australia was given self government as its own dominion and was divided into five departments derived from the previously established divisions within the colony.
Miners in the regions of Aurelia [In and around Eucla] heavily believed that it was a bad choice to not join the Commonwealth and 1902, held a referendum to secede into the Commonwealth separately as the state of Aurelia. Whether or not they were allowed to secede did not matter in the end as the referendum was only 42% for. However, it is widely believed in the Commonwealth of Australia that this referendum was rigged.
Due to the lack of tariffs, industry slowly rusted away leading up to the Great War and Western Australia became completely dependent on Primary Industries. The Great Depression further plummeted Western Australia and when commodity prices collapsed, the entire state fell into chaos. Local Strongmen rise to power and are able to keep the state together under an Authoritarian Rule. Support for the government only went up in the west coast following the Australian Civil War, in which the separatists in the Eucla area attempted to join the Commonwealth anyways and were quickly put down under threat of halting the construction of water pipelines. Essentially, the Aurelia had money in gold, but no water; while the rest of Western Australia had water and little money.
The American Empire was still supporting and benefiting from Banana republics, and was more than happy to keep Western Australia afloat. The Commonwealth shunned the Dominion, leading to the establishment of a republic in the early 60's, which became a valuable US ally.
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