The County of Brussels, also historically called the Uccle County or (County) Uccle-Brussels, was a part of the Brabant Gouw. The Brabantgouw is first mentioned in the Meerssen Convention (870), explaining that this cave consisted of four subdivisions.
The county of Brussels is located approximately between the Zenne and Dijle rivers. About the year 1000 it was linked to the Leuven County, which is believed to be thanks to the marriage between Gerberga of Lower Lorraine and Lambert I van Leuven.
It was long believed that the West Brabant area between Dender and Zenne belonged to the county of Brussels. However, it was shown that there was a German national loan. This was only acquired by the graves of Leuven around 1085/1086 in the form of a rural county. The Landgraafschap Brabant formed the basis for the Duchy of Brabant founded in 1183/1184.
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