Katherine Villiers, Duchess of Buckingham. Katherine Villiers, Duchess of Buckingham, Marchioness of Antrim, 18th Baroness de Ros of Helmsley was an English aristocrat.
The daughter and heir of Francis Manners, 6th Earl of Rutland, she was known as the richest woman in Britain outside of the royal family. She married first George Villiers, 1st Duke of Buckingham, the favourite, and possibly lover, of King James I of England; and secondly, she married the Irish peer Randal MacDonnell, 1st Marquess of Antrim.
Lady Katherine Manners was the only daughter of Francis Manners, 6th Earl of Rutland, by his first wife, Frances Knyvet, widow of Sir William Bevill of Killigarth or Kilkhampton, Cornwall, and third daughter and coheir of Sir Henry Knyvet of Charlton, Wiltshire, by Elizabeth Stumpe, the daughter of Sir James Stumpe of Bromham, Wiltshire. Katherine Manners was selected by the formidably ambitious Mary Villiers, Countess of Buckingham, to marry her son, George Villiers.
However, Manners was a strict Roman Catholic, and the King refused to allow Villiers to marry her. In addition to this, the Earl of Rutland refused to accept the Countess of Buckingham's demands for his daughter's dowry.
Manners converted to Protestantism, to satisfy the Villiers family, which almost caused her father to call off the marriage. Invited to visit the Countess of Buckingham, Katherine was forced to spend the night due to an attack of illnes