May 17, 1220 - Henry III is re-crowned at Westminster Abbey. He had been crowned at Gloucester Cathedral, aged 9, in October of 1216 after the death of his father, King John. However, the Pope didn't consider that coronation legal or carried out according to the customs of the church.
May 17, 1521 -Edward Stafford, 3rd Duke of Buckingham, is executed for treason against Henry VIII. He boasted having a better claim to the throne.
May 17, 1527 - A secret inquiry into Henry VIII's marriage with Catherine of Aragon began at Greenwich, headed by Archbishop Warham.
May 17, 1536 - George Boleyn and 4 other men are executed at the Tower, accused of treason against Henry VIII. They were convicted on trumped up charges of adultery with the Queen, Anne Boleyn.