The name Haily originates from the Old English language and is a variant of the name Haley, which itself is derived from the Old English word "hæl," meaning "healthy" or "wholesome." This name emerged during the Anglo-Saxon period in Britain, which lasted from the 5th to the 11th centuries.

Haily was primarily used as a surname in Medieval England, often referring to someone from the town of Haley or Hailey. One of the earliest recorded instances of the name can be found in the Domesday Book of 1086, where a landowner named William de Hailey is mentioned.

In the 13th century, the name Haily began to be used as a given name, particularly among the English aristocracy. One notable bearer of this name was Sir Haily de Audley, a knight who fought in the Wars of Scottish Independence in the early 14th century.

During the Renaissance period, the name Haily gained popularity across Europe, with variations such as Hailey, Hayley, and Hailee emerging in different regions. One famous bearer of the name was Haily Willbrahams, an English poet and playwright who lived in the 16th century.

In the 17th century, the Puritan movement in England led to a resurgence of biblical names, and Haily fell out of favor for a time. However, it regained popularity in the 19th century, particularly in the United States, where it was often associated with the idea of good health and well-being.

Notable individuals named Haily throughout history include Haily Selassie, the last emperor of Ethiopia, who ruled from 1930 to 1974. Another prominent figure was Haily Mills, an American actress and novelist born in 1946, best known for her roles in various Disney films.

Haily Steinfeld, an American actress and singer born in 1996, is another well-known bearer of the name. She gained recognition for her roles in films such as True Grit and Pitch Perfect 2.

Haily Vaughan, a British singer and songwriter born in 1977, is also a notable figure with this name. She has released several successful albums and is known for her unique blend of pop and folk music.

Finally, Haily Bieber, an American model and media personality born in 1996, is a recent prominent bearer of the name. She is married to Canadian singer Justin Bieber and has gained a significant following on social media platforms.