The name Niall originated from the Irish Gaelic language and has its roots in ancient Celtic culture. It is derived from the old Irish word "Niall" or "Nial," which means "champion" or "cloud." The name has been in use for centuries, with some of the earliest recorded instances dating back to the 5th century AD.

One of the most famous historical figures to bear this name was Niall Noígiallach, also known as Niall of the Nine Hostages. He was an Irish king who ruled in the late 4th and early 5th centuries. Niall is credited with leading military campaigns across Ireland, Britain, and parts of Europe, earning him the epithet "of the Nine Hostages" for the hostages he allegedly took during his conquests.

Another notable Niall in history was Niall Frossach, a 10th-century Irish king of the Northern Uí Néill dynasty. He played a significant role in the political landscape of Ireland during his reign, engaging in battles and forming alliances with other powerful clans.

In the realm of literature, the name Niall appears in some ancient Irish texts and legends. For instance, the Lebor Gabála Érenn (The Book of Invasions), a medieval Irish pseudo-historical work, mentions a character named Niall.

Niall Crosbie (1942-2013) was an Irish actor best known for his roles in films such as "Braveheart" and "The Wind That Shakes the Barley." He had a successful career in theater and television, appearing in numerous productions throughout his lifetime.

Niall Horan (born 1993) is an Irish singer-songwriter and former member of the popular boy band One Direction. After the group's hiatus in 2016, he embarked on a successful solo career, releasing chart-topping albums and singles.

Niall MacGinnis (1913-1977) was an Irish actor who appeared in several notable films, including "The Quiet Man" and "The Blood Beast Terror." He had a versatile career spanning over three decades, working in both theater and cinema.