This week I decided to look into the stamps with traditional costumes from Belgium, and to my surprise, I even found another stamp with a Dutch traditional costume. It is an Belgian airmail stamp of 1958 from a United Nations series. This series was published to commemorate the 1958 World Fair Expo in Brussels (the first one after WWII), where the first time the United Nations participated in a world fair. The UN pavilion was a blue dome with six arches symbolizing the six continents (the Americas were counted as two). Several UN organizations presented themselves: ITU, ICAO, UPU, WMO, FAO, IAEA, IBRD, IMF, GATT, ILO, UNESCO, WHO, UNICEF. This series of special UN stamps was sold as a complete series of sixteen stamps to collectors at Expo 58, the philatelic service in Brussels and at UN Headquarters in New York. The stamps could only be used on national and international mail posted at the UN pavilion. My "Dutch girl" stamp is the UNICEF one. It shows the globe with six kids from the six continents dancing around it. The Dutch girl must definitely look like a girl from Volendam and represents Europe.
But now to Belgium and its traditional costumes, and that is not easy, because not much of the traditional costumes is left. I found three stamps that could give us some idea of the traditional costumes. The first one shows a woman with her daughter and a postman from the 17th century (stamp for Stamp Day 1982); the second one shows again a woman with her daughter and a postman, but now from 1840 (stamp for Stamp Day 1975); and the third one shows a woman making lace (in two colors from the 1948 National Industries series). All three stamps show typical lace headdresses, which could be considered as typical traditional bonnets.
The last stamp is the closest I could come to a Belgian traditional costume. It shows a milk maid with her dog cart in Flanders. It is out of a series of old trades for Themabelga, the first world Stamp Exhibition for Thematical Philately in 1975. She is wearing a costume that is very similar to what lots of women in Flanders, but also in the south of The Netherlands (Zeelandic Flanders and North Brabant), were wearing with the typical large white bonnet and big shawl.
This next stamp is from 1939 and shows a woman in the traditional costume and lace cap of the Languedoc, again with a glass of wine in her hand :) She stands before the cathedral of Béziers. 
This stamp is from 1945 and celebrates the liberation of Alsace-Lorraine. The Alsace-Lorraine region is an area that switched nationality several times between France and Germany. The last time was during WW II. These two women show their French nationality by the little tricolor cockades on their traditional caps. The woman on the left wear the Alsace costume with the huge black bow cap; the woman on the right wears the Lorraine costume with the girly plied cap. They stand before the French flag, and the cathedrals of Strasbourg and Metz, respectively. 
