Iron technology was introduced into Denmark c. 500 BC and for the next 1500 years iron was produced from local bog ore. Iron working was practised in ordinary farming villages and was probably a sideline for farmers who lives where bog ore of a suitable quality and a forest large enough to supply the necessary charcoal were accessible. Even settlements such as Snorup, Starup and Drengsted, where iron was produced on a large scale, seem not to represent a society in which the main economy was based on iron working.

During the coference in Uppsala the Danish knives forged from two billets of low-carbon iron, and one billet of medium- or high-carbon iron (the sandwich technique) proved to be of particular interest. The earliest knife forged in this technique to be known so far was found at Lousgaard at Bornholm. It was deposited in a grave in the late 7th or the early 8th century.