IN JULY 1415 the warrior king, Henry V was determined to show his supremacy over the French and press his claim to the throne.

According to Shakespeare, the Dauphin, son of the king of France, had sent tennis balls to Henry. This was considered a great insult because it implied that the English king was not up to anything more than the challenge of a silly game.

Henry’s response was robust:

“When we have marched our rackets to these balls

We will in France, by God's grace, play a set

Shall strike his father's crown into the hazard.”

The preparations for an assault on France were well underway. Thousands of troops were mustered in the south of England, including 3 to 4,000 encamped on Southampton Common.

The streets of the town were thronged with troops and Southampton Water was increasingly filled with what was to become the greatest flotilla ever assembled prior to the D-Day landings.

In the middle of this feverish activity, the king learned of a conspiracy being hatched against him.

With just days to go before the departure, a second cousin, Sir Edmund Mortimer, the Earl of March, told Henry the details of a plot that would have declared Henry a usurper and made himself, the Earl of March, King instead.

Mortimer had been approached by Richard, Earl of Cambridge, Henry, Lord Scrope of Masham and Sir Thomas Gray of Heton. They planned to kill the king and replace him with Mortimer who actually had a claim to the throne which was superior to Henry’s.

Henry’s father, Henry Bolingbroke, had been banished by his cousin, the weak Richard II.

When Bolingbroke’s father, the youngest son of Edward III, died, Richard would not acknowledge the right of the young Henry to inherit the Duchy of Lancaster. Henry Bolingbroke returned to claim his inheritance initially but his popularity and support were such that he was soon declared Henry IV and deposed Richard who died in prison.

Richard was survived by a young son, Edmund Mortimer, and it was he who had been made the figurehead of a plot to put him on the throne.

Mortimer was horrified when he learnt of the details of the conspiracy. He had no ambition to be king and was quite keen to keep his head attached to his shoulders so that is why he made a clean breast of the plot to Henry at the first opportunity.

This plan paid off and it was only the three plotters who were punished. There was a hastily organised trial that may have taken place in a room at the Red Lion Inn in the High Street but is far more likely to have been in Southampton Castle.

The three men had been arrested on July 31, and imprisoned in the castle.

The initial trial took place on August 2, but Cambridge and Scrope, as peers of the realm, claimed their right to be tried by other peers so their trial had to be deferred until such a court could be convened.

Sir Thomas Gray, who was unable to claim special treatment, had already confessed and was therefore tried and executed on the same day.

The other two had not bought themselves as much time as they would probably have liked.

As most of the aristocracy of England had already arrived in Southampton in readiness for departure to France, a court of peers of the realm was easily and quickly assembled. They were tried and found guilty on the August 5.

The punishments for Cambridge and Scrope were rather different – although they both ended up dead.

Cambridge, as a grandson of Edward III, was beheaded in front of the Bargate and his head was buried along with his body in the chapel of St Julian’s Hospital ¬- also known as the French Church.

Scrope was also beheaded but his wish to be buried in York Minster was not honoured. Only his head went to York, to be exhibited on the Micklegate.

Gray’s head was similarly displayed in Newcastle.

By Ally Hayes, tour guide with SeeSouthampton.co.uk