The given name Jersen is believed to have originated from the ancient Germanic language, which was spoken by various tribes and peoples across northern and central Europe during the early medieval period. Its roots can be traced back to the Old Norse word "jærn," meaning iron, and the suffix "-sen," which was commonly used as a patronymic to indicate filiation or descent.

One of the earliest recorded instances of the name Jersen can be found in the Icelandic sagas, literary works that recount the lives and adventures of the Norse settlers in Iceland during the 9th to 11th centuries. These sagas mention a character named Jersen, who was a skilled blacksmith and weaponsmith, renowned for his craftsmanship in forging iron tools and weapons.

Throughout the Middle Ages, the name Jersen was predominately found in Scandinavian regions, particularly in Denmark, Norway, and Sweden. It was commonly used among families involved in metalworking trades, such as blacksmiths, armorers, and swordsmiths, reflecting the name's association with iron and its perceived strength and durability.

In the 12th century, a Danish warrior named Jersen Magnusson was recorded as a valiant soldier who fought alongside King Valdemar I during the Danish conquest of parts of northern Germany. Magnusson was renowned for his bravery and skill on the battlefield, earning him a place in Danish historical chronicles.

Another notable figure was Jersen Halvorsen, a Norwegian shipbuilder and explorer who lived in the 15th century. Halvorsen was credited with designing and constructing some of the sturdiest and most seaworthy vessels of his time, which aided in the exploration and trade routes between Norway and the British Isles.

In the 16th century, a Swedish nobleman named Jersen Eriksson was a prominent figure in the court of King Gustav Vasa. Eriksson served as a trusted advisor and diplomat, renowned for his wisdom and negotiation skills in forging alliances and resolving conflicts with neighboring kingdoms.

Throughout its history, the name Jersen has remained relatively uncommon, often associated with individuals from northern European descent, particularly those with ties to Scandinavian cultures and traditions. While not widely popular, it has maintained a certain cultural significance and connection to its roots in metalworking, strength, and resilience.