Frederick III of Denmark (b. 1609)

Frederick III, born on 18 March 1609, reigned as the King of Denmark and Norway from 1648 until his passing on 9 February 1670. His impactful reign is notably remembered for his pivotal role in transforming the constitutional landscape of Denmark-Norway, particularly through the establishment of absolute monarchy.

Before ascending to the dual thrones, Frederick III also held significant ecclesiastical and administrative roles. He served as the diocesan administrator, commonly known as a prince-bishop, of two important entities within the Holy Roman Empire: the Prince-Bishopric of Verden, from 1623 to 1629 and again from 1634 to 1644, and the Prince-Archbishopric of Bremen, from 1635 to 1645. These ecclesiastical territories, though nominally religious, conferred significant temporal power and influence upon their administrators, allowing Frederick to gain valuable experience in governance prior to his kingship.

Frederick was the second-eldest son of King Christian IV of Denmark and Norway and Anne Catherine of Brandenburg. Initially, he was not directly in line for the throne. The unexpected death of his older brother, Prince Christian, the designated heir, in 1647, suddenly placed Frederick in succession. To secure his election as king following his father's death, Frederick had to make substantial concessions to the powerful Danish nobility, which at the time held considerable influence within the realm's elective monarchy system.

As king, Frederick III's reign was largely defined by his strategic military engagements and sweeping constitutional reforms:

• Dano-Swedish Wars: His rule was marked by two significant conflicts against Sweden.
  • Dano-Swedish War of 1657–1658: This war concluded in a devastating defeat for Denmark-Norway, resulting in the humiliating Treaty of Roskilde in 1658. Under this treaty, Denmark was forced to cede significant territories, including Skåne, Halland, Blekinge, and Bornholm, to Sweden.
  • Dano-Swedish War of 1658–1660: Sweden's subsequent invasion, particularly the bold and unexpected Assault on Copenhagen in 1659, presented a grave threat to the monarchy. However, Frederick III demonstrated immense personal courage and resolve during the siege. His steadfastness in staying in the capital and actively participating in the defense of Copenhagen against the Swedish forces garnered him immense popularity among the common people and burgesses. This resilience ultimately contributed to Denmark-Norway's victory in this second conflict, leading to the Treaty of Copenhagen in 1660, which saw the return of Bornholm to Danish rule and Trøndelag to Norway, albeit with the definitive loss of the southern Swedish provinces.
• Institution of Absolute Monarchy: Leveraging the widespread public admiration he gained during the defense of Copenhagen and the general disillusionment with the nobility's perceived failures, Frederick III executed a revolutionary constitutional change in 1660. He successfully abolished the traditional elective monarchy, a system that had long constrained royal power, and replaced it with an absolute monarchy. This radical shift was formally codified into law with the Royal Law (Danish: *Kongeloven*) of 1665, making Denmark-Norway the first fully codified absolute monarchy in Western historiography. This new form of governance centralized all power in the monarch and remained in effect until 1848, fundamentally reshaping Danish and Norwegian society.
• Creation of the Throne Chair of Denmark: As a tangible symbol of the newly established absolute monarchy and the divine right of kings, Frederick III commissioned the ornate Throne Chair of Denmark. This magnificent piece, often associated with the Danish coronation regalia, underscored the monarch's supreme and unquestionable authority.

Frederick III married Sophie Amalie of Brunswick-Lüneburg. Their union produced several children, including Christian V, who would succeed his father as King of Denmark and Norway, continuing the line of absolute monarchs.

Frequently Asked Questions About Frederick III

When did Frederick III reign as King of Denmark and Norway?

Frederick III reigned from 1648 until his death in 1670.

What was Frederick III's most significant constitutional achievement?

His most significant achievement was the institution of absolute monarchy in Denmark-Norway in 1660, which was legally confirmed by the Royal Law (*Kongeloven*) in 1665, establishing the first codified absolute monarchy in Western Europe.

How did Frederick III come to the throne?

Frederick III was not the eldest son; he became the heir to the throne only after the death of his older brother, Prince Christian, in 1647. He then had to make concessions to the nobility to be elected king.

What role did the Assault on Copenhagen (1659) play in his reign?

The successful defense of Copenhagen during the Swedish assault significantly boosted Frederick III's popularity among his subjects, providing him with the crucial public support needed to dismantle the elective monarchy and establish absolutism.

What was the Throne Chair of Denmark?

The Throne Chair of Denmark was a ceremonial seat ordered by Frederick III, serving as a powerful symbol of the new absolute monarchy and the centralized power of the Danish king.