The Cecil Papers (ProQuest) This link opens in a new windowAn archive of approximately 30,000 sixteenth and seventeenth-century manuscripts, consisting principally of the correspondence of William Cecil, Lord Burghley (1520-1598) and his son Robert, the 1st Earl of Salisbury (1563-1612). These two men dominated the administration of government during the reign of Elizabeth I and the first eight years under her successor.