In the 18th century, a custom developed that travelling
smiths and apprentices would hammer a nail into the tree trunk; in particular, from 1715 on,
wandering journeyman locksmiths. The reason for doing so before then is unknown; however, it is unlikely to have been a
craft guild custom in the beginning, because the Stock im Eisen is significantly older. "Nail trees" are well known in Southeastern Europe and are found in many cities in
Hungary,
Romania (in
Transylvania) and other countries of the former
Austro-Hungarian Empire; the Vienna Stock im Eisen is the oldest preserved nail tree. The custom persisted until the late 19th century, and inspired the "
men of iron" statues that were used for propaganda and fund-raising in Germany and Austria in
World War I, particularly the tree set up in
Freiburg. The most likely explanation for the medieval nails is the ancient custom of hammering nails into crosses, trees and even rocks for protection or in gratitude for healing, that is as a
votive offering, similar to throwing coins into a
wishing well or a pond. In the Middle Ages, nails were a valuable commodity that people did not waste. The original mythico-religious and legal significance of the Stock im Eisen was effaced in later centuries by an emphasis on crafts. ==Legends==