The sign is found carved in a tomb
slab stood near the entrance of the cathedral of Uppsala, Sweden. It
looks like many a craftsman's cross or mark. However, it rather
seems to be a mark symbolizing the family of the buried man, born in
Stockholm and eventually professor of the university of Uppsala, quite
new at that time, who died 1494.
During the Middle Ages, and maybe well before that, craftsmen, especially masons, stone cutters, and master builders, carved their marks in their works as modern artists mark their works with their signatures.
Similar signs have been in use for many centuries as owners' marks or crosses, in Europe. Farmers used them. The cattle barons in the US used similar signs, called brands, to burn into their cattle so that every one could see to which ranch it belonged. In the Swedish countryside each farm-owning family had its farm's belongings marked with the family's special owner's cross. In Sweden these owners' crosses were formerly regarded as equally binding as a signature when drawn on a legal document. Such marks as this are for instance found carved into the doors to the benches of the St. Nicolai bishop's church in Køge, Denmark, marking where the members of different families of Køge had their seats.
Craftsmen's, farmowning families' and other families' marks or crosses are not ideograms proper, but rather like the nobility's coats of arms, a sort of graphic family names. As such they do not belong in this book. The brands by which criminals were marked already in the time of the Roman Empire, and then extensively during the Middle Ages (branding of criminals was not abolished in Denmark, for example, until 1840), would be ideograms, though, but the author has not found any data about them.
Signs very much like appear already in the neolithic age. See for instance and . Se also the modern in Group 39.