William Grant Broughton (22 May 1788 – 20 February 1853) was a British-born Anglican clergyman who served as the first and only Bishop of Australia. Broughton was born in London and began his career as a clerk at the East India Company, before graduating from Cambridge University and being ordained as a priest in 1818. He was appointed Archdeacon of the Colony of New South Wales and arrived in Australia in 1829. Upon the establishment of the Diocese of Australia in 1836, he was installed as the first Bishop of Australia.

Broughton is known for his opposition to the education reforms proposed by Governor of New South Wales Richard Bourke in 1831, modelled on the Irish National schools system. Broughton opposed moves towards religious equality and state-supported schooling, suspicious of the growing recognition and presence of the Catholic and Presbyterian churches in Australia. He believed that the Church of England should continue to enjoy special privileges as a semi-official religion within the colony. He established a number of Anglican educational institutions, including The King's School, Parramatta, and helped to expand the church's presence after the passage of the Church Act of 1836 by dedicating new church buildings, supporting the establishment of new Dioceses in Oceania, and recruiting a substantial pool of new clergy.

Broughton was a committed high churchman who opposed liberalism and the growing movement towards Catholic emancipation. He served on the New South Wales Executive Council and Legislative Council, where he played a significant role in the economic management of the colony. He was known for his conservatism and for his defence of the Church of England's special status within the growing colony.

William Grant Broughton was born on 22 May 1788 in Westminster, London. His family was not wealthy, but did have influential connections, including with Lord Robert Cecil, Marquess of Salisbury, and the Cecil family. He attended Barnet Grammar School between 1794 and 1796 and graduated from The King's School, Canterbury in 1803. He was awarded an exhibition to Cambridge University, but after the death of his father left him unable to afford to attend, he instead became a clerk for the East India Company. In 1814 he inherited a sum of money from an uncle and was able to enrol at Pembroke College, Cambridge, from which he obtained a Bachelor of Arts in 1818 followed by a Master of Arts in 1823. He graduated as sixth wrangler—the sixth-highest scoring student—after undertaking the Mathematical Tripos.

In 1818 Broughton was ordained as a deacon by Thomas Burgess, Bishop of Salisbury, and later that year was ordained to the priesthood by George Pretyman Tomline, Bishop of Winchester. On 13 July 1818 he married Sarah Francis, with whom he would go on to have three children—daughters Emily and Phoebe, and a son who died soon after his birth. Upon his ordination, he was appointed curate to John Keate, the rector of Hartley Wespall and the Headmaster of Eton College. During his time as curate to Keate he published research on the Eikon Basilike and the Greek New Testament. In 1827 he was appointed to the parish of Farnham by Charles Sumner, Bishop of Winchester, and was then given the position of chaplain at the Tower of London.

Broughton was a Tory and a high churchman, and was opposed to the growing movement towards political and theological liberalism. He was a defender of the doctrine of Apostolic succession, the importance of the Eucharist, and Royal Supremacy over the Church of England. He also held strong anti-Catholic sentiments and was an opponent of Catholic emancipation. Later in his life, he would flirt with Tractarianism—a high church or Anglo-Catholic theological movement that began at Oxford University.

In 1829, after being appointed Archdeacon of New South Wales by Prime Minister Arthur Wellesley, 1st Duke of Wellington, Broughton arrived in Sydney on the convict ship John. He was unenthusiastic about taking up the role in Australia and was reluctant to accept it, writing in his journal as he approached Sydney that "the expected termination of our voyage...occasions no sensation of joy". He moved into Tusculum, a villa in Potts Point, and was given positions on both the colony's Executive Council and Legislative Council. Broughton would go on to have a significant impact on politics in New South Wales until his retirement from the legislature in 1843, particularly in the development of its immigration and land policy, and used his experience at the East India Company to become one of the most knowledgable figures on the colony's economy. Broughton's theology placed him somewhat outside the norm in Australia, where most Anglicans were Evangelical in their beliefs. The colony's chaplain Samuel Marsden at one point said that Broughton's churchmanship made him "perhaps too high a churchman for our mixt population".

At the time of Broughton's arrival in Sydney, then part of the Diocese of Calcutta, the city had a population of 10,000 and was home to two churches: St Philip's and St James'. The Anglican church had long held a privileged position within the colony, but had begun to attract greater criticism, while the influence of the Catholic and Presbyterian churches had begun to grow. In the 1820s, the Church and School Lands Corporation had been set up to take control of one seventh of the uncleared land in the colony in order to generate income for the church. But the corporation had struggled to generate an income from its lands. Upon his arrival in Australia, Broughton learned that the Church and School Lands Corporation's charter had been suspended, and that the Anglican church's influence was waning and that the quality of church education was low. The church was reliant on funding received from the government to maintain and grow its presence in the colony.