Union of Utrecht

The Union of Utrecht (Dutch: Unie van Utrecht) is a treaty signed on January 23, 1579 in Utrecht, the Netherlands, unifying the seven northern provinces of the Netherlands, until then under control of Spain. The Union of Utrecht is regarded as the of the foundation of Republic of the Seven United Netherlands, which was not recognised internationally until the Peace of Westphalia in 1648.

The seven provinces signing the treaty were Holland, Zeeland, Utrecht, Gelderland, Overijssel, Groningen and Friesland. The treaty was a reaction of the Protestant provinces to the 1579 Union of Arras[?] (Dutch: Unie van Atrecht), in which the southern provinces (most of them now part of Belgium) declared their support for the Catholic Spanish.