Guelders
The duchy was named after the town of Geldern (Gelder) in what is now called Germany. The present province of Gelderland (English also Guelders) in the Netherlands occupies most of the area. However, the former duchy also included parts of the present Dutch province of Limburg and the territories in the present-day German state of North Rhine-Westphalia that were acquired by Prussia in 1713.