The name Keila has its origins in the Finnish language, where it is a diminutive form of the name Kaisa, which is itself a shortened version of the name Katariina, the Finnish form of the name Catherine. The name Catherine, in turn, derives from the Greek name Aikaterine, which is composed of the elements "katharos" meaning "pure" and "heiros" meaning "sacred."

The earliest recorded use of the name Keila dates back to the 16th century in Finland, where it was a popular name among the Finnish nobility. One of the earliest known bearers of the name was Keila Kaarlenpoika, a Finnish noblewoman who lived in the late 16th century and was known for her advocacy of women's education.

In the 17th century, the name Keila was mentioned in several Finnish folk songs and ballads, indicating its widespread use among the Finnish people. One such ballad, titled "Keila's Lament," tells the story of a young woman named Keila who is mourning the loss of her lover in a war.

Throughout the centuries, several notable individuals have borne the name Keila. One of the most famous was Keila Ekholm (1886-1962), a Finnish artist and illustrator who was known for her vibrant paintings of the Finnish countryside. Another notable Keila was Keila Lemetti (1905-1988), a Finnish politician and activist who fought for the rights of women and workers during the mid-20th century.

In more recent times, the name Keila has gained popularity in other parts of the world, particularly in Brazil and Portugal, where it is often spelled as "Keila" or "Queila." One of the most well-known bearers of the name is Keila Costa (born 1980), a Brazilian actress and television presenter who has appeared in numerous telenovelas and films.

Another notable individual with the name Keila is Keila Merino (born 1985), a Puerto Rican-American actress and model who has appeared in several television shows and films, including the popular series "Prison Break."

While the name Keila has its roots in Finland, it has transcended its cultural boundaries and has been embraced by people from various backgrounds and cultures, each adding their own unique touch to the name's rich history and meaning.