Perhaps the first 'Big Woman' of London

In the 13th century, the Buckerel family was one of the powers of the City of London, members of the Pepperers' Gild, which later became the Grocers' Livery Company.

"The elder Stephen was royal Chamberlain of London and King's Butler at Henry II's coronation banquet. Two years later he bought the lease of the Exchanges for three years for about 4,000 marks (£15m at present day values), and became Master of the Exchange.
... they produced the first woman known to have played a major role in City affairs in her own right. When Isabella Buckerel, wife of Stephen the younger, was widowed, she managed all her business and property affairs herself. ... holding property in the City alone which encompassed most of the Drapery, the Rpoert, the Saddlery, and the Poultry in Chepe and Walbrook and 20 other city parishes as well. She also played a behind-the-scenes part in City politics, and most of the residents of the Ward must have been dependent on her to some degree."

The Ward of Cripplegate in the City of London, Caroline Gordon and Wilfrid Dewhirst, Cripplegate Ward Club, 1985, p. 22

Typically, there appears to be nothing about her on the web.