Barrier Treaty

The "Barrier Treaties" were the names of three agreements signed and ratified during or immediately after the War of Spanish Succession. The so-called "barrier" referred to several fortresses within the territory of Spanish (later Austrian) Netherlands, that were in effect garrisons manned with Dutch troops acting as forward bases buffering the Dutch Republic from the Kingdom of France.

The first Barrier Treaty (also known as the Treaty of Den Haag or the Treaty of The Hague) was signed on 29 October 1709 between Great Britain and the states-general of the United Provinces. By the terms of the treaty, the United Provinces engaged to guarantee the Protestant succession in England in favour of the House of Hanover, while Great Britain undertook to procure for the Dutch an adequate barrier on the side of the Netherlands, consisting Dutch garrison stationed in the towns of Veurne, Nieuwpoort, Ypres, Menen, Lille, Tournai, Condé, Valenciennes, Maubeuge, Charleroi, Namur, Halle, Damme, Dendermonde and Ghent. The treaty was based on the same principle of securing Holland against French aggression that had inspired that of Treaty of Ryswick in 1698, by the terms of which the chief frontier fortresses of the Netherlands were to be garrisoned by Dutch troops.

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