Coat of Arms & Family Crest Details
J. B. Rietstap, Armorial Général, Gouda: G. B. van Goor Zonen, 1884–87
Blazon (the actual original written record)“De gu. à trois gardes d'épée d'or, avec un tronçon de la lame du même.”
A record of documented arms, meaning and origin, researched for the Mostert family of Netherlands.
J. B. Rietstap, Armorial Général, Gouda: G. B. van Goor Zonen, 1884–87
Blazon (the actual original written record)“De gu. à trois gardes d'épée d'or, avec un tronçon de la lame du même.”

The Mostert arms were recorded in Netherlands, c. 1815.
Arms such as these were typically recorded in Friesland.
Friesland was low, wet country on the northern coast of the Netherlands, farmed by families who had held the same land for centuries. Free landholders were unusually common there, and a free landholder could carry arms.
This is where the arms were entered in the register. Families often moved to other parts of the country, so the same name can turn up in more than one region.
In the Netherlands, coats of arms were often used by noble families and those who held specific public offices. These arms were passed down through the generations to legitimate descendants. Younger branches of a family usually kept the original design without needing to add special marks. This system ensured that the family identity remained clear and consistent over many years.
The family name Mostert has deep roots in the northern regions of the Netherlands, particularly within the province of Friesland. By the early 19th century, records confirm that members of the family were well-established in this area, living as part of the local Frisian community during a time of significant political change in Europe. The name itself is thought to be an occupational surname, likely derived from the Middle Dutch word for a mustard maker or a mustard seller. In medieval times, people often took their surnames from the trades they practiced or the goods they sold in the local markets. As the family grew and moved throughout the region, they maintained this identity while adapting to the evolving social and economic landscape of the Netherlands. This transition from a simple trade description to a formal family name reflects the broader history of how many Dutch surnames were standardized during the early modern period.
A pungent condiment derived from the seeds of the mustard plant.
