Recorded in many spellings including O'Kieran, O'Kerin, O' Kerrane, Kerrane, Kerin, Kerins, and probably others, this is a surname of medieval Irish origins. It derives from the pre 10th century Gaelic Ciar, a personal name meaning black or dark brown. In early times a clan of this name controlled the greater part of the present barony of Costello, County Mayo. Today, the name is still very popular in this county but in the spellings of Kearns and Kerran. In the medieval period, the name spread to the neighbouring counties of Sligo and Donegal where it is sometimes found as Kerr. In the early 15th century a branch of the clan settled in County Clare, becoming O' Kerin, Kerin and Kerins. The tomb of Teige O' Kerin who died in 1685 can be seen in Ennis Abbey. An interesting namebearer was Father Moses Kearns, who lived an exciting life. In 1792 he survived being hanged by the revolutionary mob in Paris (the clergy being very unpopular), through the breaking of the rope. He then moved back to Ireland to become one of the leaders of the 1798 rebellion in County Wexford. The first recorded spelling of the family name is shown to be that of Owen O'Kerin, which was dated 1420, in the records of County Clare, during the reign of King Henry Vth of England, known as the Victor of Agincour, 1413 - 1422. Surnames became necessary when governments introduced personal taxation. In England this was sometimes known as the Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.