During the Middle Ages, blacksmiths were at the heart of all urban and rural societies. The iron and steel objects they produced were used by all levels of society, from simple peasants to the highest nobility.

The blacksmith's role is to shape raw materials (iron or steel). To do this, he heats the iron in a powerful fire fuelled by a bellows. The oxygen in the fire allows it to reach very high temperatures. The metal becomes malleable when hot, and the blacksmith can then strike it with a hammer on an anvil. To determine the temperature of the steel, the blacksmith relies on the colour of the metal. At 650°C, the iron turns cherry red. It then turns bright red, orange, yellow and finally white (at around 1100°C).

Depending on the type of object being manufactured, the blacksmith may also use different heat treatments to change the structure of the steel. These heat treatments include normalisation, annealing, quenching and tempering.

The production of iron and steel was a long and costly process. Its use was reserved for objects requiring its strength and hardness. From the 13th century onwards, the European Middle Ages experienced a small metallurgical revolution. The use of mechanised bellows and hammer mills, both powered by water wheels driven by rivers, led to a considerable increase in production and thus spread its use among the population.

The blacksmith will make objects according to need. In times of peace, he will make tools for working in the fields or for craftsmen, domestic objects, or shoe horses. In times of war, he will make weapons (swords, spears, arrowheads) and armour.

His rare and essential expertise earns him the respect and esteem of the population.