The district was created in 1975 by merging former districts Dinslaken, Moers and Rees, which were all created in 1816 when the area became part of Prussia. Its capital is Wesel, its most populated city is Moers.
The coat of arms show a willow tree with 13 branches representing the 13 municipalities and cities in the district. The green color as well as the tree was chosen to show that the city is surrounded by a green belt. The coat of arms was granted in 1978.