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January 26th marks the day when in 1788 the First Fleet of British ships arrived at Port Jackson, New South Wales and the Flag of Great Britain was raised at Sydney Cove by Governor Arthur Phillip.
http://www.abc.net.au/news/2018-01-25/australia-day-first-fleet-should-be-remembered-on-january-26/9360398
The date is somewhat controversial amongst the first Australians, the indigenous community calling it "Invasion Day". There is a very strong movement at present to change the date of Australia day for this reason. I am somewhat sympathetic to this change.
I have to say that the significance of the date January 26 has been somewhat lost in recent years with the encouragement of Aussies to get out on Australia Day and enjoy the outdoors in celebration of being Australian.
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