Thorn was an independent state for more than eight hundred years, where female monks led by a queen abbess held sway. Count Ansfried founded a monastery for Benedictines at a height close to the Meuse around 990. Ansfried's daughter, later called Benedicta in tradition, became the first abbess of this monastery. This Thorn Abbey developed from the 12th century into a secular monastery, a monastic community in which the rules of order were interpreted liberally. Only unmarried women from the high nobility could enter the ladies' hall. Women within the order who wanted to marry lived outside the monastery walls in their own houses. Many of the homes of these Stift ladies have been preserved. The monastery grew into a small independent principality, the Abbey Principality of Thorn. This was the smallest sovereign state within the Holy Roman Empire. Thorn suffered greatly under the French. Then Thorn also got its characteristic white color. After the noble ladies fled in 1794, the French imposed a tax based on the size of the windows. The poor population, often living in large buildings that had previously belonged to rich people, could not afford this. To limit the amount of the tax bill, the windows were bricked shut. With the aim of hiding these construction traces, the houses were whitewashed.