The name Ciara has its roots in the Irish Gaelic language and is derived from the word "ciar," meaning "black" or "dark." It is believed to have originated as a descriptive name, possibly referring to someone with dark hair or complexion.

In medieval Ireland, Ciara was a common name among the Celtic population. One of the earliest recorded instances of the name dates back to the 7th century, when a Saint Ciara (also spelled Cera or Cyra) lived in County Tipperary, Ireland. She is venerated as the patron saint of breastfeeding mothers.

During the Middle Ages, the name Ciara was also found in various Irish annals and manuscripts, indicating its widespread use among the Irish nobility and religious orders. For example, the Annals of Ulster mention a Ciara ingen Duib in the year 923 AD.

Throughout history, several notable individuals have borne the name Ciara. One of the earliest was Ciara ingen Duinnchuan (c. 828 – 891), an Irish princess and abbess who founded the monastery of Killeedy in County Limerick. Another was Ciara ingen Ruaidri (c. 1050 – 1112), a poet and scholar who lived during the reign of the High King of Ireland, Muirchertach Ua Briain.

In more recent times, the name Ciara gained popularity in the late 20th century, particularly in the United States and Ireland. One of the most famous modern-day bearers of the name is American singer and songwriter Ciara Princess Harris (born in 1985), known professionally as Ciara.

Other notable individuals named Ciara include Irish actress Ciara O'Callaghan (born in 1977), British journalist Ciara Hunt (born in 1982), and Irish swimmer Ciara Carragher (born in 1995), who represented Ireland at the 2016 Summer Olympics in Rio de Janeiro.

While the name Ciara has its origins in Irish Gaelic, it has transcended cultural boundaries and is now found in various parts of the world, albeit with variations in spelling and pronunciation.