Here are some key events of the day:
* The Commonwealth of Australia Constitution Act was proclaimed, formally establishing the new nation.
* The first Governor-General, Lord Hopetoun, was sworn in, representing the British monarch as the head of state.
* The first Prime Minister, Edmund Barton, was sworn in along with his cabinet, forming the first federal government.
* Celebrations took place across the nation to mark this momentous occasion.
This day is now commemorated as Australia Day, a national holiday celebrated on January 26th in most states and territories.