Lady Catherine Grey (sometimes spelled "Katherine") (August 1540 - January 26, 1568), Countess of Hertford, was the second surviving daughter of Henry Grey, 1st Duke of Suffolk and Lady Frances Brandon. She was the younger sister of Lady Jane Grey and older sister of Lady Mary Grey.

Her maternal grandparents were Charles Brandon, 1st Duke of Suffolk and Mary Tudor, former Queen consort of France. Mary was the daughter of Henry VII of England and Elizabeth of York and the younger sister of Henry VIII of England.

Catherine was married to Henry Herbert, son of William Herbert, 1st Earl of Pembroke in May 1553, on the same day as her sister Jane was married to Guilford Dudley. After the wedding Catherine went to live with her husband at Baynard's Castle on the Thames.

Jane Grey was the designated heir of Edward VI of England, son of Henry VIII by his third queen consort Jane Seymour. Edward VI died on July 6, 1553 and Jane was proclaimed Queen regnant on July 10. However Edward VI had removed his older half-sisters Mary I of England , daughter of Henry VIII by his first queen consort Catherine of Aragon, and Elizabeth I of England, daughter of Henry VIII by his second queen consort Anne Boleyn, from the line of succession.

Jane was deposed in favour of Mary on July 19, 1553. The Earl of Pembroke sought to distance himself from the Grey family and cast out Catherine from his home and had her unconsummated marriage annulled. The deposed Queen was executed on February 12, 1554. Mary continued to reign until her natural death on November 17, 1558. She was also the second queen consort of Philip II of Spain. Mary died childless and was succeeded by her younger half-sister Elizabeth.

Elizabeth was herself unwed and childless. The matter of her succession would bring Catherine Grey to relative prominence. As a grand-daughter of Mary Tudor, Catherine had a valid claim to the throne of the Kingdom of England. Under Henry VIII's will she could claim to be next-in-line for the throne and was therefore as significant a threat to Queen Elizabeth as Jane had been to Queen Mary. However, at one point the queen seemed to be warming to Catherine, as a potential Protestant heir, and it was rumoured that she was considering adopting her.

During her time at the court of Queen Mary, Catherine had become friendly with Jane Seymour, daughter of Edward Seymour, 1st Duke of Somerset and niece of the deceased Queen Jane Seymour. Through Jane, Catherine met her brother Edward Seymour, 1st Earl of Hertford, and fell in love with him. In December 1560, Lady Catherine secretly married Edward Seymour. The wedding was conducted at Edward's house in Canon Row, and Jane Seymour was the only witness. There was no formal record of the marriage.

Queen Elizabeth, unaware of the marriage, sent Edward away to France with Thomas Cecil, eldest son of William Cecil. The two were to tour Europe as a way to improve their education. Seymour left with his wife a document which would, in the event of his death, allow her to prove the marriage and inherit his property. Catherine, however, lost the document. Thus, when the always frail Jane Seymour died of tuberculosis, Catherine was not only left alone and friendless at court; she also had no means of proving her marriage.

Catherine concealed the marriage from everyone for months, even after she proved to be pregnant; when eight months pregnant and on progress with the court in Ipswich, she saw no choice but to seek help from influential court members. She first confessed to Bess of Hardwick, Lady Saintloe; however, Bess, convinced that both herself and Catherine would die for such treachery, not only refused to aid Catherine, but cursed the unfortunate girl for ever having told her such a secret. Catherine followed this by secretly visiting Robert Dudley, brother-in-law to her dead sister, in his bedroom at night, and pleading with him for help. Dudley also refused to help her; and then, fearful of the Queen discovering the visit and suspecting an affair, he immediately told Elizabeth everything he knew.

Elizabeth was greatly angered that her cousin had married anyone without her permission, and did not approve of her choice of husband. Catherine was imprisoned in the Tower of London, where Edward joined her on his return to England. Even Bess of Hardwick was imprisoned, as Elizabeth became convinced that the marriage was part of a wider conspiracy.

The marriage was annulled in 1562 but resulted in two children, both of whom were born in the Tower : *Edward Seymour, Lord Beauchamp of Hache (1561–1612). * Thomas Seymour (born 1563).

Lady Catherine died at Cockfield Hall http://www.ngfl.ac.uk/tudorhistory/index95.html and was buried in the Cockfield Chapel in Yoxford church in Suffolk. Her children were regarded as ineligible to succeed to the throne because of the annulled marriage, which made them illegitimate. However, in Elizabeth I's and later James I of England's reigns, they were courted as potential successors to the crown.

It was this Edward Seymour, styled Lord Beauchamp, whose son, (Catherine's grandson) William Seymour, 2nd Duke of Somerset, later got into trouble by his secret marriage to Arbella Stuart, another cousin with a claim to the throne of England.

*Chapman, Hester W. Two Tudor Portraits: Henry Howard, Earl of Surrey and Lady Katherine Grey. Jonathan Cape, 1960.

* Catherine at Cockfield Hall — Tudor Place

* Lady Anne Stanley

Grey, Catherine Grey, Catherine Grey, Catherine Grey, Catherine Grey, Lady Catherine Grey, Lady Catherine Grey, Lady Catherine