The Constitution of Australia is the law that set up the Australian Commonwealth Government and says how it works. It is made up of several documents. The most important is the Constitution of the Commonwealth of Australia. The people of Australia voted in referendums from 1898–1900 to accept the Constitution. The Constitution was then passed as a part of the Commonwealth of Australia Constitution Act 1900 (Imp), an Act of the Parliament of the United Kingdom. Queen Victoria signed it on 9 July 1900. The Constitution became law on 1 January 1901. Even though the Constitution was an Act of the United Kingdom parliament, the Australia Acts took away the power of the United Kingdom parliament to change the Constitution. Now only the Australian people can change it by referendum.