Matthiasen is a Danish patronymic surname meaning "son of Matthias." Patronymics were once widespread across Scandinavia, where children took their father's first name followed by a suffix indicating descent (–sen for sons, usually –datter or –sen for daughters). In Denmark, patronymics were gradually replaced by inherited family surnames from the late 19th century, yet many such names remain common today. Matthiasen thus places its bearers directly in the Danish onomastic tradition. The root name Matthias derives ultimately from the Greek Ματθίας (Matthias), a variant of Ματθαῖος (Matthaios), which is the source of Matthew. In the New Testament, Matthias was the apostle chosen to replace Judas Iscariot after the betrayal of Jesus, according to the Acts of the Apostles 1:23–26. The name has been borne by several European royals, notably Matthias I Corvinus (Mátyás in Hungarian), king of Hungary in the 15th century who expanded his realm through military campaigns and fostered Renaissance culture. Distribution and Variants As a surname, Matthiasen is most frequently found in Denmark, with possible minor occurrences in Norway and among expatriate communities. Variant Mathiasen uses the alternate spelling Mathias in place of Matthias. Cognates in other languages include Matevosian and Matevosyan (Armenian), Mateev/Mateeva (Bulgarian), Mateu (Catalan), and Matić (Croatian), all of which stem from the same personal name. Meaning: “son of Matthias” Origin: Danish patronymic Type: Surname Usage regions: Denmark, Scandinavia