Maria Winifreda Francisca Howard, Duchess of Norfolk (née Shireburn; b. circa 1693 d. 26 September 1754), was the wife of Thomas Howard, 8th Duke of Norfolk.
The only surviving child and heir of Sir Nicholas Shireburn, 1st and last Baronet, of Stonyhurst, she was born into a prominent Catholic Lancashire family. She was sixteen years old when she married the Duke of Norfolk on 26 May 1709. She brought a large dowry of more than £30,000. When her husband was arrested on 29 October 1722 under suspicion of involvement in a Jacobite plot and imprisoned in the Tower of London, the Duchess was not allowed to visit him. She nevertheless managed to convince the Earl of Carlisle to act as surety for his bail in May 1723.
The 34 piece silver-gilt toilet service made in 1708, and presented by her father to the Duchess of Norfolk on her marriage was granted an export licence to Australia in 2012, despite objections by the Victoria and Albert Museum. It was valued at £1,380,000.
The childless marriage was, however, unhappy due to the Duchess's strong Catholic and Jacobite feelings. She left him when he, as she put it, "truckled to the Usurper".
Widowed on 23 December 1732, the Duchess married Peregrine Widdrington in November 1733. He was the brother of William Widdrington, the 4th and last Baron Widdrington of Blankney, and had taken part in the Jacobite Rising of 1715. She died in 1754, as the last representative of her family.