The name Alienor has its origins in the medieval French language, derived from the Germanic elements "alli" meaning "other" and "nor" meaning "vigor" or "nobility." It was a popular name among the French aristocracy during the 11th and 12th centuries.

The earliest known bearer of the name was Aliénor d'Aquitaine (1122-1204), one of the most powerful and influential figures of the Middle Ages. As Duchess of Aquitaine, she was one of the wealthiest and most prominent women in Europe, and through her marriages to King Louis VII of France and King Henry II of England, she played a significant role in the politics and culture of the time.

Another notable Alienor was Aliénor de Provence (1223-1291), Queen of England as the wife of King Henry III. She was known for her patronage of the arts and her influence on English culture, including the introduction of the use of the French language at court.

In the 14th century, Aliénor de Comminges (1329-1397) was a powerful noblewoman who served as the Countess of Comminges and Viscountess of Lautrec. She played a significant role in the political affairs of the region and was known for her intelligence and diplomatic skills.

During the Renaissance, Aliénor d'Estampes (1498-1530) was a French noblewoman and the mistress of King Francis I of France. She was renowned for her beauty and her influence over the king, and was a prominent figure in the French court during this period.

In the 17th century, Aliénor d'Arcy (1617-1654) was a French author and playwright who wrote several works in the style of the "précieuses," a literary movement that emphasized refinement and elegance in language and behavior.

Throughout its history, the name Alienor has been associated with nobility, elegance, and cultural influence, reflecting the prominent role that many of its bearers played in the courts and societies of their time.