Marlborough, Sarah Churchill, duchess of, 1660–1744, confidante of Queen Anne of England. Born Sarah Jennings, she was a childhood friend of Princess Anne. In 1677 she married John Churchill, later 1st duke of Marlborough. On Anne's marriage (1683) she was appointed lady of the bedchamber and became a close confidante. Although temporarily out of favor (1692–94) owing to the political disgrace of her husband, Sarah maintained a close relationship with Anne (who succeeded to the throne in 1702) until 1705, when they began to quarrel over Whig cabinet appointments. Until then Sarah had wielded considerable influence at court, but gradually Abigail Masham, a kinswoman both of Sarah herself and of the Tory leader Robert Harley, replaced her in Anne's affections. Finally dismissed in 1711, she and her husband went abroad in 1713. After the death (1722) of the duke of Marlborough, the duchess supervised completion of the building of Blenheim Palace, quarreling bitterly with its architect, Sir John Vanbrugh, and with most of her relatives.