When William IV died on 20 June 1837, his niece Victoria became queen of the United Kingdom of Great Britain and Ireland at the age of 18, although her coronation did not occur until 28 June in the following year. In 1840 she married Prince Albert of Saxe-Coburg and Gotha, and in the first ten years of her marriage she survived five assassination attempts. Her popularity in Ireland waned after the potato blight of 1845-9 resulted in widespread famine, exacerbated by British government policies.
In 1851 the British government decided to separate the Port Phillip District of south eastern Australia from the Colony of New South Wales, creating the Colony of Victoria. Prince Albert died of typhoid fever in 1861 as a result of poor sanitary conditions at Windsor Castle, and the queen wore black for the rest of her life. Victoria became Empress of India in 1876 when the British government took over direct administration of India from the British East India Company.
After a decade of consultations, the colonies of Australia achieved federation on 1 January 1901, becoming the Commonwealth of Australia. The Colony of Victoria became the State of Victoria. Three weeks later, on 22 January 1901, Queen Victoria died of a cerebral haemorrhage, at the age of 81. She had reigned as queen for 63 years and 7 months, making her the longest-serving British monarch.