Starting in the 19th century, there has been a long-term movement towards legal and societal equality for women, removing restrictions such as them voting or owning property. In the 1970s, European monarchies began questioning their laws that give men preference in succeeding to the throne over their elder sisters; the first such change passed in Sweden in 1979, reversing the order of succession between the infant children of King Carl XVI Gustaf, princess Victoria (b. 1977) and prince Carl Philip (b. 1979).

Even in a realm like Spain, which legally still uses male-preference primogeniture, it is expected that Infanta Leonor will ascend to the throne once the reign of her father, King Felipe VI, ends.

Besides Princesses Victoria and Leonor, who are first in the line in their respective nations, Princess Elisabeth of Belgium and Princess Catharina Amalia of the Netherlands are heiresses apparent, so also first in line, while Princess Ingrid Alexandra of Norway is second in line, behind her father, Crown Prince Haakon.

The question is also true if other women alive as of January 02, 2022 are the monarchs. For example, Victoria is a generation older than the other princesses, and has a daughter of her own, Estelle. Leonor has a younger sister, Infanta Sofía. The other three European constitutional monarchies - Denmark, Luxembourg and the United Kingdom - have only men in the direct, most likely succession line so are excluded from this question; and the other monarchies in Europe (Andorra, Liechtenstein, Monaco and the Vatican City) are considered too small to matter for our purposes, besides other complexities.

For reference, here are the years of birth of the people in question, beginning with the current Kings:

• Belgium: Filip (1960) – Elisabeth (2001)

• Netherlands: Willem-Alexander (1967) – Catharina-Amalia (2003)

• Norway: Harald V (1937) – Haakon (1973) – Ingrid Alexandra (2004)

• Spain: Felipe VI (1968) – Leonor (2005)

• Sweden: Carl XVI Gustaf (1946) – Victoria (1977) – Estelle (2012)