[1] The plot was hatched and planned by Charles de Mornay, a Swedish courtier of French Huguenot origin with international contacts.
In the summer of 1572, the French envoy to Denmark, Charles de Dançay, conducted secret negotiations with unidentified Swedish aristocrats about a deposition of John III of Sweden.
[3] Charles de Mornay contacted Archibald Ruthwen and Gilbert Balfour, the commanders of the Scottish mercenary troops which arrived in Sweden in June 1573.
In late October, the Scottish mercenaries left Sweden to serve in the Livonian War in Swedish Estonia.
Another important witness was Duke Charle's English servant Sigfrid Preston, and the testimonies of the Scottish mercenaries, notably that of Gilbert Balfour.
However, it is noted, that the suspected conspirators Hogenskild Bielke, Gustaf Banér and Pontus De la Gardie, often gathered at meetings in the apartment of Princess Elizabeth of Sweden, meetings where Princess Cecilia of Sweden had also frequently been seen, and the two sisters and their brother Charles were somewhat compromised though they were never accused.
[3] On 29 August, Charles de Mornay was sentenced guilty as charged for treason against king John III as well as having caused the execution of the innocent Hugh Cahun.
[2] Duke Charles was, if not an active participant so at least aware of the plot without trying to prevent it – but his part in the affair was silenced by order of the king.