Niall is a male given name of Irish origin. The original meaning of the name is unknown,^[1] but popular modern sources have suggested that it means "champion" (derived from the Old Irish word niadh).^[2] According to John Ryan, Professor of Early and Medieval History at University College Dublin, Niall "seems to be so ancient that its meaning was lost before records began."^[1]

Medieval times

• Niall of the Nine Hostages, High King of Ireland who lived in the early-to-mid 5th century AD
• Niall Caille, High King of Ireland in the 9th century AD

Modern times

• Niall Carolan (b. 2002), Irish Gaelic footballer
• Niall Ferguson (b. 1964), Historian and the Laurence A. Tisch Professor of History at Harvard University^[3]
• Niall Horan (b. 1993), a member of the British-Irish boy band One Direction^[4]
• Niall Mackenzie (b. 1961), Scottish former professional motorcycle road racer
• Niall Matter (b. 1980), Canadian actor
• Niall McCready, Irish Gaelic footballer
• Niall McGinn (b. 1987), Northern Irish footballer
• Niall Moran (b. 1983), Irish hurler
• Niall O'Brien (b. 1981), Irish cricketer
• Niall O'Donnell (b. 1998), Irish Gaelic footballer
• Niall Quinn (b. 1966), Irish former international footballer and chairman of the English club Sunderland A.F.C.

Fictional characters

• Niall, a Circle Mage from Dragon Age: Origins
• Hunter Niall from Sweep
• Niall Brigant from The Southern Vampire Mysteries
• Niall MacDonnell from the Honorverse
• Niall Rafferty from Hollyoaks
• Niall from Xenoblade Chronicles 2
• Pedron Niall from The Wheel of Time
• Commander Niall from Elden Ring

• List of Irish language given names
• Neil, Nigel, probable cognates through Norse, medieval Latin and Anglo-Norman borrowings.