Peacock & Son was a tanning and wool-brokering business in the early days of South Australia. Three members of the family were notable public figures: William Peacock (c. 1790 – 20 January 1874) was a successful businessman and one of the colony's first parliamentarians. His eldest son Joseph Peacock (c. 1825 – 25 July 1867) carried on the family business and was a member of parliament. His youngest son Caleb Peacock (13 April 1841 – 17 February 1896) was a member of parliament and Mayor of Adelaide from 1875 to 1877, the first such born in the Colony.
William and family sailed for South Australia on the "Glenalvon", a ship he chartered, arriving at Holdfast Bay on 28 December 1838.
William commenced his tannery business in Grenfell Street in 1839, with a fellmongering facility at Adam Street, Hindmarsh. He had moved by 1868 to Thebarton His was the first major tannery, ahead of both Dench & Co. and G. W. Bean, and the first to export acacia bark. The Adam Street property was sold in July 1903 to fellmongers Michell and Sons.
He was one of the original investors in the South Australian Mining Association, which developed the lucrative Burra copper mines between 1845 and 1865, and a director (disqualified in 1860 through absence greater than 6 months but subsequently re-elected)
He was associated with the Congregational Church in Freeman Street (now part of Gawler Place), funded the building of the chapel in Ebenezer Place (off Rundle Street east). He then helped organise the building of the Hindmarsh Square Congregational Church, which later became an office and orchestral studio for ABC Radio. He was closely associated with J. L. Young and his Adelaide Educational Institution, which for many years used rooms at the Ebenezer Place and Freeman Street chapels.