Act of Seclusion

The Act of Seclusion was an Act of the States of Holland, required by a secret annex in the Treaty of Westminster (1654) between the United Provinces and the Commonwealth of England in which William III, Prince of Orange, was excluded from the office of Stadtholder. The First Stadtholderless Period had been heralded in January 1651 by States Party Regenten, among whom the republican-minded brothers Cornelis and Andries de Graeff and their cousins Andries and Cornelis Bicker, during the Grote Vergadering (Great Assembly) in The Hague, a meeting of representatives of the States of each of the United Provinces. This meeting was convened after the death of stadtholder William II on November 6, 1650, when the States of Holland decided to leave the office of Stadtholder vacant in their province.

Through the Treaty of Westminster Johan de Witt, Grand Pensionary of Holland, not only ended the First Anglo–Dutch War, but also ensured that the Orangist regent faction would be much weakened, so that English Republicans no longer needed to fear that William III (four years of age at the time) could become a strong Dutch leader who could bring the Stuarts to whom he was closely related through his mother Mary, Princess Royal and Princess of Orange, back on the English throne. Ironically, William III would later drive out the Stuart King James II during the Glorious Revolution and thereby end moves in England towards absolutism.

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