After the States General of the Netherlands had concluded the peace treaty, called the Pacification of Ghent, with the rebelling provinces of Holland and Zeeland on 8 November 1576, thereby throwing down the gauntlet to the government of the overlord of the Habsburg Netherlands, king Philip II of Spain, the royal stadtholder of Flanders Jan van Croÿ chose the side of the rebels and helped the citizens of Ghent subdue the Spanjaardenkasteel in the city. However, when the new royal governor-general of the Netherlands, Don Juan of Austria arrived in the country, Croÿ resigned his post, and was replaced by Philippe III de Croÿ, duke of Aarschot by appointment of the States General. However, Aarschot was a prominent Roman Catholic and therefore not trusted by the Calvinists in Ghent. On 28 October 1577 the Ghent magistracy under the leadership of two prominent Calvinists, Jan van Hembyse and François van Ryhove performed a Coup d'état with the tacit approval of the Prince of Orange and took power in Flanders. Aarschot, the grootbaljuw of Ghent, and the bishops of Bruges and Ypres were arrested. Previously a similar coup had taken place in the capital of the Duchy of Brabant, Brussels and there the city government had been taken over by a Council of 18 members, called the Achttienmannen. Ghent similarly now installed a similar council for its new government, also called the Achttienmannen. Hembyse became the chairman of this council with the title of First Schepen. Hembyse had the support of the noted Calvinist clergymen Petrus Dathenus and Herman Moded who helped him keep control of the Calvinist "mob". He armed the citizens of Ghent and hired Scottish mercenaries. This gave him the military means to conquer a number of other Flemish cities where similar Calvinist city republics, governed by councils of Achttienmannen were formed. The Ghent Calvinists were not interested in Orange's "religious peace", but wanted to persecute their Catholic opponents as stringently as the Catholics had previously persecuted the Calvinists. Hembyse and Ryhove orchestrated an Iconoclastic Fury in Ghent in May 1578 after rumors of sodomy by monks of a local Catholic monastery had spread. The monks were arrested, tried, and convicted and sentenced to be burned at the stake. These persecutions, and also the terror of the Scottish mercenaries who mercilessly looted the Flanders countryside, provoked a Catholic reaction, led by the faction of the Malcontents, that eventually would cause the secession of the Walloon provinces, who were united in the Union of Arras and concluded a separate peace with the Spanish Crown at the Treaty of Arras in May 1579. The Union of Arras was countered by the defensive Union of Utrecht and the Ghent Republic joined that union already on 4 February 1579. King Philip was declared to have vacated the throne on 6 August 1579. The Ghent magistracy assumed his sovereign powers for the city republic.
End
Meanwhile, there was a falling out between Hembyse and Ryhove, and Ryhove managed to have Hembyse exiled from the city after in December 1578 Orange came to the city and reformed its magistracy. Orange also managed to impose his "religious peace" in Ghent. Ryhove received the office of grootbaljuw as representative of Orange. But the military situation in Flanders gradually worsened for the Calvinists and the Flemish members of the Union of Utrecht. The Malcontents joined the reconquest of Parma, the new royal governor-general and his Army of Flanders, and together they besieged and conquered more and more of the Flemish cities. On 24 October 1583 there was a new coup in the Ghent city government, in which Ryhove was defeated and exiled, and Hembyse returned to power. Ryhove then took up a blocking position in Dendermonde between Antwerp and Ghent, and cut off the supply lines to the city from Antwerp. The Spanish army laid siege to Ghent, while Hembyse held dictatorial powers in the city. He negotiated in secret with the Spaniards, and when this was discovered by the enraged citizens he was arrested, tried for treason, and on 8 August 1584 executed. Ghent had to surrender to Parma on 17 August 1584, ending the reign of the Calvinist Republic.
