|— Territory of the Unified Royal States of Australis —|
|Annexed from Australia||15 October 2020|
|- Grand Duke of Australis||Daniel I|
|- Prime Minister of Australis||Rory McPhail|
|Elevation||25 m (82 ft)|
|Time zone||Australissian Central Time (UTC+8:00)|
North Constantia is a territory of the Unified Royal States of Australis. It is composed of the northern portion of Constantia, a small island situated 700 metres from the shoreline of Hamelin Bay, Western Australia. Macronationally, the island is known as Hamelin Island. It was annexed entirely by Australis on 15 October 2020, and later the southern half of the island was ceded to the Commonwealth of Naveria.
There is currently one abandoned building on the island; an abandoned light station built in the 1930's.
In Latin, the word Constantia means constant. The name was chosen by the Deputy Minister for Foreign Affairs of Australis, Brayden 'Lee' Eaves.
During the late 1930's, a small light station was constructed on the island in order to facilitate navigation of Cape Leeuwin, the most south-westerly point on the Australian continent. It was also used to guide cargo ships into the Hamelin Bay, where they would berth at the Hamelin Bay jetty, constructed for the local timber industry. 
During a surveying expedition near to Jarrahview, the ceremonial capital of Australis, the island was sighted and marked for annexation by the Grand Duke of Australis, who viewed the island as a perfect territory to claim, due to its size and proximity to the mainland. A colonisation expedition is scheduled to take place during December 2020, during which the Grand Duke would travel across to the island via boat and raise the Australissian flag. 
On 29 November, Casper von Naveria and Daniel Hamilton, representing the Commonwealth of Naveria and the Unified Royal States of Australis respectively, reached an agreement to split the island of Constantia between the two nations as a form of diplomacy. In the deal, Australis ceded the southern portion of the island to Naveria, naming it South Constantia, and Australis kept the northern half of the island, naming it North Constantia.