On this day in Tudor history, 20th April 1534, in the reign of King Henry VIII, prominent citizens of London were required to swear the Oath of the Act of Succession.

Chronicler Charles Wriothesley explained that all the guilds were called to their halls to swear:

To be true to Queen Anne (Anne Boleyn) and to recognise her as Henry VIII’s lawful wife and the rightful Queen of England.
To think of the king’s eldest daughter Mary as illegitimate.