"Mary Tudor was the most hated queen in British history. During her five-year reign, she threw all England into chaos. Mary beheaded 'traitors,' murdered 'heretics,' and had pregnant women burnt to death in the name of her religious fanaticism. The entire nation lived in fear of her. Thousands fled into hiding, and the streets of English cities were polluted with the putrid smell of burning flesh. She created such terror that she's known as 'Bloody' Mary."
"Introduction to a Discovery Channel documentary about Mary"

Mary I (February 18th, 1516 – November 17th, 1558) was the Queen of England and Ireland from July 1553 until her death. Her opponents gave her the name "Bloody Mary".

She was the only surviving child born of the ill-fated marriage of Henry VIII and his first wife Catherine of Aragon. Her younger half-brother, Edward VI, succeeded Henry in 1547. When Edward became mortally ill in 1553, he attempted to remove Mary from the line of succession because of religious differences. On his death, their cousin Lady Jane Grey was at first proclaimed queen. Mary assembled a force in East Anglia and successfully deposed Jane, who was ultimately beheaded. In 1554, Mary married Philip of Spain, becoming queen consort of Habsburg Spain on his accession in 1556.  As the fourth crowned monarch of the Tudor dynasty, Mary is remembered for her restoration of Roman Catholicism after the short-lived Protestant reign of her half-brother. During her five-year reign, she had over 280 religious dissenters burned at the stake in the Marian Persecutions. Her re-establishment of Roman Catholicism was reversed after her death in 1558 by her younger half-sister and successor, Elizabeth I.