My name is Marcus De Geer. I am a Swedish citizen living in St. Louis. I believe the family has been known since the 1200's in the old region of Brabant. The De Geer family was originally Flemish, and they were Wallonians skilled in iron mining. Louis De Geer moved to Sweden in the 1600's on invitation from the Swedish king GustafIIAdolf in order for him get help with the minig industry. It was a great success, and the king could produce guns for the 30 years war that was going on in Europe at the time. The family was knighted and has ever since been part of the Swedish House of Nobles. During the centuries, there have been several prominent members of the family, among others the very first state minister of Sweden, Louis De Geer (in the middle of the 1800's), who by the way was my great great grandfather. Hope this information has been helpful.