Jensen (surname)

Jensen
Family name
Meaning	"Son of Jens"
Region of origin	Germany and Denmark
Related names	Johnson

Jensen is a Surname of German and Scandanavian origin. Jensen literally means son of Jens. It is the most common surname in Denmark, where it is shared by about 5% of the population. It is also very common in other Scandinavian countries such as Norway, where it is the ninth most common surname, but nevertheless shared by about 5% of the population. The name is also in use in the Faroe Islands.

There was no "Jensen family," merely a system of patronymics that was finally fixed in the 19th century at an arbitrary time, when the state bureaucracy required a more rational system; before that people took their name from their father's first name.

...
Wikipedia