Quilty is an Irish family name which has spread throughout the English-speaking world.
The name "Quilty" is an Anglicized form of the ancient Gaelic name of "Caoilte" (pronounced: Kweelteh). There was a mythic Celtic warrior (c. 3rd Century A.D.) by the name of Caílte mac Rónáin, who was a member of the Fianna and the nephew of Fionn mac Cumhaill. According to legend he lived long enough to be baptized by St. Patrick (c.389-461). The book "If You're A Wee Bit Irish: a chart of old Irish families collected from folk tradition" by William Durning (1978) recounts an alleged ancestry of Caoilte back to Adam. James Joyce (1882–1941) in chapter twelve of his masterpiece, Ulysses, (1922) has "The tribe of Caolte" as one of the twelve tribes of Ireland in a biblical parallel to the twelve tribes of Israel. The name is considered a sept of the dynastic Dál gCais of the Kingdom of Thomond, and has the motto "Lámh Ládir an Nachtar" meaning "the strong hand uppermost."
There are various spellings of the name: Caoilte, Caolte, and Cuallta in Gaelic, and Kielty, Kealty, Keelty, Keilty, Kelty, Kilty, and Quilty (with or without an O' or Mc or Mac) in English. The most common variants are Kielty and Quilty.
Edward MacLysaght writes in his 1964 book Supplement to Irish Families, that Quilty is a Munster name that has been mistakenly translated from the Irish word caol (slender) or coillte—plural of Irish word coill (wood)[1] . Coillte is the namesake of a town named Quilty located in the County Clare.
The first documented reference of a Quilty is given in a 1313 Justiciary Roll under the reign of Edward II (also known as Edward of Caernarfon). In this record an unnamed O'Kilte is mentioned as a servant of a Nobleman named John Harold. Where in Mowan, Lymerick when they were robbed of "two affers worth 20s".[2]
In 1850 there were over 75 families bearing the name of "Quilty" in Ireland, over half of them in County Limerick. As of 2005, there were about 300 families bearing the name of "Quilty" in the United States alone, almost half them in the northeast, with the highest concentrations in the states of Massachusetts, New York, Florida, Illinois, and California.