The woman who wrote the oldest surviving English valentine in 1477 was Margery Brews.
Margery Brews was an English gentlewoman from Norfolk who corresponded with John Paston III during their courtship. Her letters survive in the Paston Letters, a major collection of fifteenth-century family correspondence. In letters written around February 1477, she addressed John as her “right well-beloved Valentine” and eventually signed herself “your Valentine.”
The surviving correspondence is both romantic and practical. Margery was trying to persuade John—and their families—to continue negotiations for marriage, despite disagreements over family approval and the size of her dowry. The couple married soon afterward and had at least three children.
“Oldest surviving English valentine” can be misleading if it is taken to mean the oldest valentine anywhere. The earliest surviving valentine is generally identified as a French poem written by Charles, Duke of Orléans, to his wife while he was imprisoned in England after the Battle of Agincourt. Margery Brews is specifically linked to the earliest surviving English romantic letters, not the earliest surviving valentine in every language.