Prehistory and origin of Stockholm
According to the Chronicle of Eric, written in the 1320s, Stockholm was founded by Birger Jarl around 1250 as a lock to the Lake Mälaren region ("laas fore then sio", "lock before that lake") in order to prevent pirates from reaching the seven cities and nineteen parishes around it. Another medieval source ("Visbyannalerna"), however, claims the city was founded in 1187 following a pagan pillaged the city of Sigtuna, and as there was an "Earl" named Birger around at that time too, the disputed origin of the city are likely to remain obscure and some historians choose a diplomatic interpretation saying there was some sort of fortification around by the mouth of lake Mälaren when the city was founded during the second half of the 13th century. As Snorri mentions no city in his account but some sort of fortification called a "kastali" (in various manuscripts curiously said to be located east and west of "Stocksund"), it has generally been assumed this fortification eventually developed into the castle Tre Kronor located where still is the Stockholm Palace.
Stockholm University
In 1878, the university college "Stockholms högskola" started its operations with a series of lectures on natural sciences, open to curious citizens (a tradition still upheld by yearly publicly open lectures). Notable in the university's early history is the appointment of Sofia Kovalevskaya to hold a chair in mathematics department in 1889, making her the third female professor in Europe. In 1904 the college became an official degree granting institution.
In 1960, the college was granted university status, becoming Sweden's fourth state university. The university premises were situated in central Stockholm at "Observatorielunden" but increased enrollment resulted in a lack of space, which required the university campus to be shifted to a bigger facility. Since 1970 most of the university operations are pursued at the main campus at Frescati north of the city center, the former
Experimentalfältet, previously used by the Royal Swedish Academy of Agriculture and Forestry.