Walsingham, Sir Francis (1530?-1590), an English politician, was secretary of state to Elizabeth I from 1573 until his death. He advocated policies that were opposed to Spain. After 1569, Walsingham operated an efficient secret service organization that discovered and broke many plots against Elizabeth. He exposed the Babington Plot (1586), which eventually led to the execution of Mary, Queen of Scots. Walsingham was born in Chislehurst, in the county of Kent.