Old Windsor was once the site of an important palace of the Saxon Kings. The settlement is documented as a defended royal manor in Edward the Confessor's time, but archaeological evidence suggests royal connections had existed since at least the 9th century. The Saxon royal site was excavated between 1953 and 1958, and the finds are at Reading Museum. Edward gave the manor to the Abbot of Westminster in 1066, but it was soon taken back into royal possession by William the Conqueror. Old Windsor was popular with the monarch because of its convenient location; near to the river for transport and Windsor Forest for hunting. Old Windsor was also an early minster location and market, probably associated with a lock, and important riverside mill complex. The Saxon palace was eventually superseded by the Norman Windsor Castle, at 'New' Windsor. The medieval manor house, however, became a popular royal hunting lodge while the castle was still a fortress rather than a comfortable residence.

At the southern end of the village, is the historic Beaumont Estate. First mention of the estate is recorded around the year 1300, when the estate, and much of the surrounding area was under the ownership of Hugo de Remenham. The estate was, at the time, known as Remenham, and occupied a larger area that it does now, stretching all the way down to the river, and including the historic pub, the Bells of Ouzeley. After changing hands a few times, the estate was bought by Henry Frederick Tynne who had the house redesigned in 1705 by architect James Gibbs, renamed it Bowman's Lodge. The estate was acquired in the mid-eighteenth century by Sophia, Duchess of Kent. In 1751 the estate was bought by the Duke of Roxburghe for his son, the Marquess of Beaumont, who renamed it Beaumont Lodge. It was bought in 1786 by Warren Hastings, the first Governor-General of India, and most notable resident of the estate, for £12,000. In 1790, the owner Henry Griffith had Windsorian architect Henry Emlyn rebuild, and modify the house. The estate was sold in 1805 for £14,000 to Viscount Ashbrook, a friend of George IV. After the Viscount's death in 1846, the Bells of Ouzeley pub was sold by his widow, and in 1854, she sold the estate to the Society of Jesus, who used it as Beaumont College. In 1861 it became the St. Stanislaus College, Beaumont; a Catholic boarding school for boys. In 1967, the school closed, and moved to merge with Stonyhurst College, in Lancashire. The estate was subsequently bought by the computer company ICL, and then by Hayley Conference Centres, in 2003.

A chapel at Beaumont is said to be the inspiration for the chapel in Evelyn Waugh's Brideshead Revisited. Waugh spent time in Windsor, whilst in the armed forces.

Windsor Great Park is largely within the bounds of Old Windsor, including both the Royal and Cumberland Lodges.