The merged municipality of Ruisbroek developed on one of Brabant's most important rivers, the Senne. In the Middle Ages, Ruisbroek was already connected to the pilgrimage city of Halle, Brussels and Uccle by important trade routes. The village was then divided into several parts by the Brussels-Charleroi canal, the railway and the TGV line and the Brussels-Mons motorway.
 
In the 12th century there were several place names in circulation: 'Ruschebruc, 'Russebusch', 'Ruskebroch', 'Ruschebruc' and finally 'Rusbroeke'. From 1491 the name 'Ruisbroeck' was applied. These toponyms are important evidence of earlier agricultural activities: a "trousers" is a swamp, drained by human labor and turned into pasture, and "rusch" or "ruisch" is a species of piping that grows in water. Due to the construction of the 74 km long canal (1827-1832) or "canal", the industry developed at a high level and the population increased sharply.
 
One of Ruisbroek's most famous sons was Jan van Ruusbroec (1293-1381). At the age of eleven, he fled to Brussels and settled with his uncle and priest, Jan Hinckaert. He studied at the chapter school, was chaplain of St. Gudula Church for 26 years, and then retired to a vault in the Sonian Forest. It was there that he founded Groenendael Abbey and had all kinds of profound experiences of God. Legend has it that it happened under a burning linden tree. He wrote several treatises, letters and mystical works. Many works were later translated into Latin, French, German or English and inspired other members of the clergy. He is rightly considered the most important writer of the 14th century in Dutch and Brussels. Jan van Ruusbroec died in 1381, as prior of the aforementioned monastery.