Thomas was Elizabeth's son by her first marriage, to Sir John Grey. He was created Marquess of Dorset on April 18, 1475 and summoned to Parliament on November 15, 1482. In January 1482/3 on the death of his grandmother Elizabeth, he became Lord Ferrers of Groby. He joined the Duke of Buckingham's 1483 rebellion against Richard III. When the rebellion failed he fled to Brittany to join Henry Tudor, the future Henry VII.
Thomas first married Anne of York, dowager Duchess of Exeter and sister of Edward IV. After she died without children he married Cecily Bonville, Baroness Harington and Bonville. By the latter marriage Lady Jane Grey was his great-grand-daughter.
He is depicted in William Shakespeare’s play Richard III.
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|width="30%" align="center"|Preceded by:
New Creation
|width="40%" align="center"|Marquess of Dorset
|width="30%" align="center" rowspan="2"|Followed by:
Thomas Grey
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|width="30%" align="center"|Preceded by:
John Grey
|width="40%" align="center"|Baron Ferrers of Groby
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