The history of Alençon is rooted in deep antiquity, yet its emergence as a significant settlement began in the early Middle Ages. The city originated in the 4th century during the Christianisation of the region, but its actual development as a fortified centre is linked to the 10th century. The first documentary mentions describe Alençon as a strategic point under the control of the powerful dynasty of the Lords of Bellême. It was they who laid the foundation for the first fortress, around which the city began to expand.
Several circumstances contributed to transforming Alençon into an important regional hub. The city is situated in a fertile valley, at the confluence of the Sarthe and Briante rivers, which provided natural defence and access to waterways. Alençon was located on the border between Normandy and the County of Maine, making it a vital trade and defensive outpost. A special role was played by the acquisition of the status of a duchy in the 15th century (in 1414), which attracted nobility and contributed to an architectural flourishing.
The economy of early Alençon was based on agriculture and crafts. Thanks to its favourable location, the city quickly became a centre for trade fairs, where merchants flocked from neighbouring regions. By the Middle Ages, traditions of textile production began to form here. Local craftsmen specialised in processing flax and hemp, creating high-quality fabrics. These early artisanal skills subsequently became the foundation for the emergence of the famous Alençon lace, which later brought the city global fame.