Sir Francis Walsingham (c. 1532 – 6 April 1590) was principal secretary to Queen Elizabeth I of England from 20 December 1573 until his death and is popularly remembered as her "spymaster".
Born to a well-connected family of gentry, Walsingham attended Cambridge University and travelled in continental Europe before embarking on a career in law at the age of twenty. A committed Protestant, during the reign of the Catholic Queen Mary I of England he joined other expatriates in exile in Switzerland and northern Italy until Mary's death and the accession of her Protestant half-sister, Elizabeth.
Walsingham rose from relative obscurity to become one of the small coterie who directed the Elizabethan state, overseeing foreign, domestic and religious policy. He served as English ambassador to France in the early 1570s and witnessed the St. Bartholomew's Day massacre. As principal secretary, he supported exploration, colonization, the use of England's maritime strength and the plantation of Ireland. He worked to bring Scotland and England together. Overall, his foreign policy demonstrated a new understanding of the role of England as a maritime Protestant power with intercontinental trading ties. He oversaw operations that penetrated Spanish military preparation, gathered intelligence from across Europe, disrupted a range of plots against Elizabeth and secured the execution of Mary, Queen of Scots.