Hólar was founded as a diocese in 1106 by bishop Jón Ögmundsson and soon became one of Iceland's two main centers of learning. Hólar played an important part in the medieval politics of Iceland, and was the seat of Guðmundur Arason in his struggle with Icelandic chieftains during the time of the commonwealth. Under Jón Arason Hólar was the last remaining stronghold of Catholicism in Iceland during the Reformation. The best known Lutheran bishop of Hólar was Guðbrandur Þorláksson.
The first printing press was introduced to Hólar in 1530. Hólar Agricultural College was founded 1882. The college was renamed Hólar University College in 2003. Among others, some of the world's at the time best instructors and trainers of the icelandic horse are educated at this college.