Sir William Stanley was an English soldier and the younger brother of Thomas Stanley, 1st Earl of Derby

Thomas Stanley, 1st Earl of Derby

Thomas Stanley, 1st Earl of Derby, KG was titular King of Mann, an English nobleman and stepfather to King Henry VII of England...

. Stanley fought with his troops in several battles of the Wars of the Roses

Wars of the Roses

The Wars of the Roses were a series of dynastic civil wars for the throne of England fought between supporters of two rival branches of the royal House of Plantagenet: the houses of Lancaster and York...

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He was born at Lytham, Lancashire, the younger son of Thomas Stanley, 1st Lord Stanley. In 1465 he married Joan, daughter of the first Viscount Beaumont

Baron Beaumont

The title of Baron Beaumont is an ancient one in the Peerage of England, created in 1309 for a younger part of the de Brienne-family. The sixth Baron Beaumont was created Viscount Beaumont in 1432; after the death of the 2nd Viscount both titles fell into abeyance...

, and widow of John, Lord Lovel

Baron Lovel

There have been four baronies and one viscountcy created in the name of Lovel or Lovell.-Baron Lovel, of Titchmarsh :* John Lovel, 1st Baron Lovel * John Lovel, 2nd Baron Lovel died at Bannockburn...

. He married secondly, c.1471, Elizabeth Hopton, daughter of Thomas Hopton with whom he had a daughter, Jane Stanley.