The name Jensen is a Scandinavian name with origins tracing back to medieval Denmark and Norway. It derived from the Old Norse name Jenssøn, which means "son of Jens". Jens, in turn, is a form of the name Johannes, the Scandinavian equivalent of John.

The earliest recorded instances of the name Jensen date back to the 13th century in Denmark. It was initially used as a patronymic surname, indicating the father's given name. Over time, Jensen transitioned from being a surname to also being used as a given name in its own right.

One of the earliest known individuals with the name Jensen was Jens Jensen, a Danish chronicler who lived in the late 13th century. He is known for his work Ældste Danske Krønike, which documented the history of Denmark from its mythical origins to the year 1288.

In the 16th century, Jensen Bjelke was a Norwegian nobleman and military leader who played a prominent role in the Swedish-Danish Wars. He served as a commander in the Danish army and was instrumental in several key battles against Swedish forces.

In the realm of literature, Jens Peter Jacobsen (1847-1885) was a Danish novelist and poet who is considered a pioneer of the Naturalist movement in Scandinavian literature. His novel Niels Lyhne is regarded as a seminal work in Danish literature.

In the 20th century, Jens Christian Skou (1918-2018) was a Danish chemist who received the Nobel Prize in Chemistry in 1997 for his discovery of the sodium-potassium pump, a critical mechanism for the transportation of ions across cell membranes.

Another notable figure with the name Jensen was Jens Nygaard (1926-2002), a Norwegian computer scientist who co-designed the influential programming language SIMULA, one of the first object-oriented programming languages. His contributions were pivotal in the development of modern computer programming.

While the name Jensen has its roots in Scandinavia, it has since gained recognition and usage in various parts of the world, particularly in regions with strong Danish or Norwegian cultural influences.