Solution

You must have noticed: the death of the Lord Chamberlain was not natural. A crime was committed that night. Everything leads us to identify a poisoning: an unknown red powder, brought back from a foreign country, and likely to provoke a heart attack. But, who would be able to commit this murder? And for what reason?

Don Salluste is probably the only one who has nothing to reproach himself for. In love for a long time with Marguerite, he met objections from Jan Sweerts, her uncle, who didn’t regard him as an eligible match. He could count on the help of Capuzzi who organised a secret rendezvous with Marguerite during the banquet. Not wanting to wait much longer, Marguerite convinced Don Salluste to run away with her during the night.

Marguerite hasn’t much to blame herself for either. She was a witness to several weird come-and-goes around the person of Louis Chabot de Beaulieu, as well as strange phenomena near Brother Ambrosius’ chamber. However, she did give a copy of her uncle’s secret diary, in exchange for some help organising a secret rendezvous in the gardens with her lover, Don Salluste. She run away with the latter just before the banquet, without knowing about her uncle’s fate.

The Countess of Glastonbury has no interest to eliminate the Lord Chamberlain, quite the contrary in fact. The King of England sent her on a secret mission at the Court: she had to arrange a secret meeting with the Emperor, convincing him to an alliance with Henry VIII against France, and thus undermining Charles the Fifth’s whish for neutrality. The Countess managed to convince the Lord Chamberlain, who promised to bring Charles the Fifth to a secret meeting during the banquet. Sadly, Jan died before doing it. While waiting in vain for Jan, she saw John of Saxony and Ambrosius leave the palace, disguised as monks.

Jan Sweerts, Lord Chamberlain of the Court, is the victim of a poisoning more political than personal. The only things to be hold against him are his wish to protect his niece and the organisation of a meeting between the Countess and the Emperor against the promise of a personal gratification.

Bernardo Capuzzi, under cover of being an artist, is in fact a spy of the Pope at the Imperial Court. He had to insure the stay of the Empire in the bosom of the Church. Nostalgic of Italy, he hoped that a remarkable feat would allow him a return to Rome. He became the accomplice of the French Ambassador against the knowledge of the real identity of the Alchemist Hohenheim, actively wanted by the Church. The artist manipulated Marguerite Sweerts to get the diary of the Lord Chamberlain and bought the red powder from Don Salluste, officially to use it as a pigment for an unfinished painting. When he learned about the true identity of Hohenheim, the latter had already fled the Court.

Brother Ambrosius is passionate about alchemy and medicine, he wrote a couple of treatises under the name of Hohenheim. After the Church condemned his texts, he found refuge with the Elector of Saxony, Frederick III the Wise. The latter being more and more in opposition with Charles the Fifth, he was afraid of his nephew John of Saxony being used as hostage in case the situation turned badly for him. That is why he sent Brother Ambrosius as a messenger to convince his nephew to flee the Court.
Ambrosius is the one who analysed the red powder and identified it as a poison. Sadly, someone stole the results of his research from him. He couldn’t identify the illness of the Lord Chamberlain, having already fled the palace by that time.

John of Saxony committed several mistakes in this affair, which made him an involuntary accomplice, because of his dissolute live. Drunken, he told an Ambassador’s spy about the meeting of the Countess and the Lord Chamberlain. Having many debts, he accepted the money of Louis Chabot de Beaulieu against the promise to serve French wine to the Lord Chamberlain. Wine from the much talked-about poisoned bottle that was fatal to the Chamberlain.
John accepted to follow Brother Ambrosius to avoid being held as hostage. The two accomplices left the palace disguised as monks, knowing nothing about the Chamberlain’s death.

The culprit of this whole affair is Louis Chabot de Beaulieu, the French Ambassador. He acted for a political reason. Since his arrival at the Brussels’ Court, he had to make sure there wouldn’t be an alliance between the Empire and England. Such an alliance would greatly weaken the influence of France. Knowing about the secret meeting arranged by Jan Sweerts between the Countess and the Emperor, he decided to have the Lord Chamberlain eliminated in order to cancel the meeting. Therefore, he used the red powder, Brother Ambrosius having recently discovered its properties as poison. In order to know that, Louis had the Grimoire of the Alchemist stolen by his spy, Rodolphe. 

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