The name Kaitlynn is a modern variation of the traditional Scottish name Caitlin, which is derived from the Gaelic name Caitlíona. The Gaelic name Caitlíona is believed to have originated from the Greek name Aithalione, meaning "little battlemaiden" or "little fighter."

The name Caitlín first appeared in written records in the late 16th century, primarily in Ireland and Scotland. It was a popular name among the Celtic cultures and was often associated with strong-willed and independent women. The spelling variation "Kaitlynn" is a more recent development, likely emerging in the 20th century.

While the name Caitlín has deep roots in Celtic history and mythology, there are no known direct references to it in ancient texts or religious scriptures. However, the name's meaning and association with strength and resilience resonate with the warrior spirit celebrated in Celtic folklore and legends.

One of the earliest recorded instances of the name Caitlín can be found in the 17th century, when it was the name of an Irish noblewoman, Caitlín Dubh, who was a prominent figure in the Confederate Wars of the 1640s. Another notable bearer of the name was Caitlín Ní Uallacháin (1800-1873), an Irish poet and storyteller known for her contributions to preserving Irish oral traditions.

In more recent times, the name Kaitlynn has been carried by several famous individuals, including Kaitlynn Carter (born 1988), an American blogger and influencer; Kaitlynn Bristowe (born 1985), a Canadian television personality and former contestant on "The Bachelor"; and Kaitlynn Lawes (born 1988), a Canadian Olympic gold medalist in curling.

Other notable individuals with variations of the name include Caitlin Moran (born 1975), a British journalist and author; Caitlin Doughty (born 1984), an American mortician and author known for her advocacy for death acceptance; and Caitlin Stasey (born 1990), an Australian actress and advocate for women's rights.

The name Kaitlynn, with its rich Celtic heritage and associations with strength and resilience, has endured through the ages and continues to be a popular choice for parents seeking a name with a touch of historical significance and a sense of empowerment.