The county emerged about 1096, when Gerard III of Wassenberg was first documented as "Count of Guelders". It was then located on the territory of Lower Lorraine, in the area of Geldern and Roermond, with its main stronghold at Montfort (built 1260). Count Gerard's son Gerard II in 1127 acquired the County of Zutphen in northern Hamaland by marriage. In the 12th and 13th century, Guelders quickly expanded downstream along the sides of the Maas, Rhine, and IJssel rivers and even claimed the succession in the Duchy of Limburg, until it lost the 1288 Battle of Worringen against Berg and Brabant.