Henri de Fleury de Coulan, Sieur de Buat, St Sire et La Forest de Gay (died October 11, 1666) was a captain of horse in the army of the Dutch Republic, who became embroiled in a celebrated conspiracy during the First Stadtholderless Period to overthrow the regime of Grand Pensionary Johan de Witt in favor of future Stadtholder William III, known as the Buat Conspiracy. He was convicted of treason in 1666 and executed.
The conspiracy was romanticized in the novel "Elisabeth Musch" (1850), by Jacob van Lennep
The Dutch poet Constantijn Huygens wrote the following epitaphOP BUAT, ONTHOOFT II. OCT. 1666. EX LATINO MEO
Hier light een schuldigh man, van Hooft en Hals berooft,
Die, doen hij schuldigh weird, een’ hals had, maer geen hooft.
which may be translated as:
Here lies a guilty man, deprived of head and neck,
who, when he became guilty, did have a neck, but not a head
Ritmeester Buat (1968) was a Dutch TV series with actor Coen Flink in the role of Buat
Henri Buat (as he is usually known; the Anglicized first name "Henry" that is sometimes found in the literature, is not correct) was the son of colonel Philippe Henri de Fleury de Coulan (or Culan), a Huguenot officer, commanding an infantry regiment of French mercenaries in the service of the Dutch Republic, and Esther de Flins.
Not much is known about his early life. He became a page at the court of the Stadtholder as a boy. He then made a career in the Dutch army, like his father, but in the cavalry. He became a captain commanding the Eskadron Gardes du Corps (Life Guards of the Stadtholder) on November 16, 1646. After the suspension of the Stadtholderate this became the Gardes te paard van de Staten van Zeeland (Horse Guards of the States of Zeeland) in 1660. This was a regiment of horse, paid for by the province of Zeeland, a province that was ambivalent in its attitude to the aspirations of the Orangist party. This may explain why Buat became attached to the court of young William III in the early 1660s, while still commanding the regiment, despite the fact that officially the Dutch government of the day frowned on the aspirations of the Orangists.
Buat distinguished himself during the landing of Dutch troops on the Danish island of Funen during the Dutch intervention in the Northern Wars in 1659.
He married Elisabeth Maria Musch (not to be confused with her sister Maria Elisabeth), a daughter of the former secretary of the States-General of the Netherlands under the Stadtholderate Cornelis Musch, and Elisabeth Cats, a daughter of Grand Pensionary Jacob Cats in 1664. This marriage tied him even closer to the Orangist cause, because the Musch family were ardent Orangists.
In 1666, during the Second Anglo-Dutch War, Buat became involved as a messenger in secret correspondence between Sir Gabriel Sylvius, then at the court of Charles II of England but earlier a member of the court of William III's late mother, Mary Stuart, when she was still alive, on the one hand, and members of the entourage of the Prince on the other. Sylvius was acting on behalf of Lord Arlington, a minister of Charles II. The correspondence was originally a diplomatic "back channel" between the Dutch and English governments to explore possibilities of peace. Grand Pensionary De Witt was therefore fully aware of the correspondence, and it had his tacit approval.
However, Arlington and Sylvius had further designs in case the tentative peace negotiations would not bring the desired results. They plotted to bring about an Orangist coup d'état in the Republic, which would overthrow the De Witt regime, restore the stadtholderate, end the war, and renew the Anglo-Dutch friendship. Sylvius imprudently committed full details of this plot to paper in a letter for Buat personally, which he sent to Buat, together with other letters which were intended for the eyes of De Witt. Buat got confused and handed this compromising letter over to De Witt, together with the more innocent ones. When he discovered his mistake he went back to De Witt to ask the "wrong" letter back, but it was already too late: De Witt had rendered the incriminating letter to the States of Holland for further action.
Buat was now arrested (though he was given time to burn most of the incriminating letters, the drafts of which were later discovered in the English state archives). In the criminal procedures that followed it transpired that besides Buat only two Rotterdam regents, Johan Kievit and Ewout van der Horst, had sufficiently compromised themselves to be charged also. Both escaped to England and were tried in absentia.
Buat, however, had the misfortune to be tried for treason by the Hof van Holland (the main court of the province of Holland). This in itself was controversial, as the asserted treason was against the Generality, so that the Hoge Raad van Holland en Zeeland (the federal supreme court) might have been more appropriate. Also, according to the opinion of many contemporaries and some later historians, the Executive in the form of the States of Holland exerted undue influence in the proceedings.
Many, then and now, think that Buat did not have the intent to commit treason but was the naive stooge of more sinister parties. Nevertheless, the facts were clear, and the verdict was harsh: he was convicted, after one of the judges who might have voted in his favor (Jacob van der Graeff, the father of the would-be assassin of Johan de Witt, who was executed in 1672), had been forced to recuse himself, tipping the balance in the court, and sentenced to death. The sentence was publicly executed by Christiaan Hals, the Hague headsman, on October 11, 1666.