St. Lambertus of Maastricht was a 7th-century bishop known for his role in spreading Christianity in the region of Maastricht, which is now part of the Netherlands. He is often associated with the establishment of churches and the promotion of religious education among the local population. His efforts contributed to the growth of the Christian community in the area. Lambertus is also recognized as a martyr, having been killed in 705 AD due to conflicts with local rulers. His legacy is celebrated in various regions, and he is venerated as the patron saint of Maastricht and Liège. His feast day is observed on September 17.