William's father Robert was a grocer in Lincoln, where William was born, and already a respected figure there before moving to Maidenhead on Christmas Eve, 1826 where he opened a general provisions store on the High Street. After his apprenticeship to a chemist in Lincoln, William returned to Maidenhead in 1840 and developed the brewing business started by his father at the back of the shop. In 1848, William married Sarah Saunders, daughter of another High Street grocer and they had four children.
When Robert died in 1853, William took effective control of the brewing business (although his stepmother was the owner) registering it first as the Pine Apple Steam Brewery (named for the first pineapple grown in England at Dorney Court) but soon changing it to Nicholson's Brewery and moving the works to the site of the stables and coach house of the demolished White Hart Inn.
Nicholson's Brewery thrived and grew, changing its name again in the 1870s to Nicholson & Sons when William's sons Robert, Frederick and Francis entered the business. The brewery was a major employer in Maidenhead and the focal point of the town centre with its high brewing tower, accompanying chimney and the imposing High Street Façade.
William moved from the house adjacent to the brewery to a house called the Elms on Castle Hill but by 1891 had remarried after his wife died had moved again to Haydon Lodge on the corner of Boyn Hill Avenue and Grenfell Road (known today as Haydon Court and divided into flats). In 1907, the Elms became the Girls' High School and remained so for 50 years. When, in 1957, the school moved out to become Newlands, the Elms became a youth centre until 2008.
William was a keen cricketer and footballer being a member of a Maidenhead team of 18 (!) which beat an all-England Eleven brought down by John Wisden (in which Wisden, Lillywhite and Adams took part) in 1853 in a two-day match in Kidwells Park.
He was elected to the town council and appointed alderman in 1876 but was never Mayor. When he retired from the council in 1904 he donated £1,000 to buy the land on which was built the first free public lending library in Maidenhead, funded by the philanthropist Andrew Carnegie. It was replaced by the present building in 1973.
William’s wife Sarah died in 1881 and seven years later he married Elizabeth Cail, 21 years his junior. He died on April 11 1916 aged 96 and is buried in the churchyard of All Saints' Boyn Hill.
Nicholson & Sons was bought by Courage in 1958 and the buildings demolished, but William Nicholson's name lives on in the Nicholson Centre shopping precinct built on the site of the brewery, Nicholson's Lane by the Methodist Church which once led into the brewery complex and in the Nicholson Local Studies Room at Maidenhead Library, with his portrait at the entrance.