Line of succession to the Danish throne

The Danish Act of Succession, adopted on 27 March 1953, restricts the throne to those descended from Christian X and his wife, Alexandrine of Mecklenburg-Schwerin, through approved marriages. Succession is governed by absolute primogeniture.

Dynasts lose their right to the throne if they marry without the permission of the monarch, to be given in the Council of State. Individuals born to unmarried dynasts or to former dynasts that married without royal permission, and their descendants, are excluded from the throne. Further, when approving a marriage, the monarch can impose conditions that must be met in order for any resulting offspring to have succession rights. Should there be no eligible descendant of King Christian X and Queen Alexandrine, the parliament has the right to elect a monarch and determine a new line of succession.

The consent to Princess Benedikte's marriage to Prince Richard of Sayn-Wittgenstein-Berleburg in 1968 was given on the condition that their children (and further descendants) would take up permanent residence in Denmark upon reaching the age of mandatory schooling. Since the condition was not met, Princess Benedikte's children are not deemed to have succession rights and are not included in the official line of succession. It is unclear when exactly they lost their succession rights, whether their own descendants will have succession rights if raised in Denmark and whether their exclusion from the line of succession is constitutional, leading the Danish jurist Henrik Zahle to argue that the children of the Princess of Sayn-Wittgenstein-Berleburg do have succession rights.

Before 1953, various descendants of King Christian IX had succession rights in Denmark. The new Act of Succession terminated those rights but left the individuals involved in possession of their titles. This created a class of people with royal titles but no rights to the throne. As a distinction, those entitled to inherit the throne are called "Prins til Danmark" (Prince to Denmark, although this distinction is not made in English) while those without succession rights are referred to as "Prins af Danmark" (Prince of Denmark).

From 1853 until 1953, the crown passed according to agnatic primogeniture. The monarch in 1953, King Frederick IX, had three daughters but no sons. Under the 1953 act, the heir presumptive to the throne was Hereditary Prince Knud, the King's younger brother. The Hereditary Prince was far less popular than the King was. Further, his mother-in-law, Princess Helena, was accused of supporting the Nazi movement during the Second World War. These factors, combined with a belief that the Salic Law was outdated, resulted in the movement to change the succession law so that Frederick's eldest daughter, the then Princess Margrethe, could inherit the throne. Thus, the Salic law was changed to male-preference primogeniture in 1953, meaning that females could inherit, but only if they had no brothers.

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