Thomas Howard, 4th Duke of Norfolk, is arrested for his role in the Ridolfi plot to assassinate Queen Elizabeth I of England and replace her with Mary, Queen of Scots.

Thomas Howard, 4th Duke of Norfolk,, was an English Roman Catholic nobleman and politician. He was a second cousin of Queen Elizabeth I and held many high offices during the earlier part of her reign.

The Ridolfi plot was a Catholic plot in 1571 to overthrow Queen Elizabeth I of England and replace her with Mary, Queen of Scots. The plot was hatched and planned by Roberto Ridolfi, an international banker who was able to travel between Brussels, Rome and Madrid to gather support without attracting too much suspicion.

Elizabeth I was Queen of England and Ireland from 17 November 1558 until her death in 1603. She was the last and longest reigning monarch of the House of Tudor. Her eventful reign, and its effect on history and culture, gave name to the Elizabethan era.

Mary, Queen of Scots, also known as Mary Stuart or Mary I of Scotland, was Queen of Scotland from 14 December 1542 until her forced abdication on 24 July 1567.

September 7 is the 250th day of the year in the Gregorian calendar; 115 days remain until the end of the year.