Traditionally seen as a key governing entity of the now-destroyed world of Alderaan, the High Council acted as a crucial support for the planet's well-known democratic structure, despite the existence of a constitutional monarchy. Although the Royal House of Alderaan, particularly the House of Organa near the end, had direct authority over the High Council, the Council itself embodied representation from all sentient beings residing on Alderaan at that time. It is believed that Alderaan's vizier was also a member of the High Council.
Throughout their lives, the future rulers of the Alderaanian throne were required to deeply understand the complexities of social justice and political governance; most of them held positions both in the Galactic Senate of Coruscant as their planet's representative (though occasionally individuals outside the royal family, such as Senator Bail Antilles, occupied this role), and on the High Council.
According to the script of Star Wars: Episode IV A New Hope featured in the Star Wars: Behind the Magic interactive database, Leia Organa was depicted as a member of the "Alderaan Senate".