Recorded as the very rare McQuilty, Quilty, Keelty, Keeltagh and O'Kielt, this is an Irish surname. It originates from the pre 10th century Gaelic surname O' Caoilte meaning the male descendant of Caol, a nickname for a slender person, from caol meaning small or slight, or from coillte meaning woods or forest and hence a topographical name for a resident in a wooded area. The form as (Mc)Quilty is mainly to be found in the province of Munster and especially in County Limerick, whereas, the variants Kielty and Keetlty are more widespread in Connacht. Kiety, Keeltagh and O'Kielt are also used in Ulster as Gaelic forms of the name Small, because of the "caol" association. Examples of recordings include examples such as that on June 6th 1848, of Elizabeth Kielty, born at Ballinderryn in County Derry. The first recorded spelling of the family name is shown to be that of Taeg O' Kilte and dated 1313 in the records known as the Justiciary Roll of County Limerick, during the reign of King Edward 11nd, and known as "Edward of Caernafon", 1307 - 1327. Surnames became necessary when governments introduced personal taxation. In England this was sometimes known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.