This unusual surname is of Irish origin, and is an Anglicized form of the Old Gaelic "Mag Fhionnghaile", son of Finonnghaile, a male given name composed of the elements "fionn", four, and "gaile", the genitive of "gal", ardour, valour. Traditionally, Irish family names are taken from the heads of tribes, revered elders, or some illustrious warrior, and are usually prefixed by "O", male descendant of, or "Mac", denoting "son of". The form "Mag" (as above) is used before names beginning with vowels or an aspirated F. The great MagFhionnghaile sept originated in the province of Ulster, where the surname was initially Anglicized "MacGinley". The prefix "Mac" was dropped at the period of Gaelic submergence, and the forms Ginley, Ginnaly, Ginnelly, Ginnally and Gonn(el)ly emerged. Several of the name MacGinley were notable churchmen, and are mentioned in Records of the diocese of Raphoe, County Donegal. In the 16th Century a branch of the Donegal MacGinleys moved to County Westmeath, and from thence to County Mayo where the name took the form Ginnelly. On December 2nd 1864, the birth of Michael, son of Dennis Ginnelly and Mary Keane, was recorded in Binghamstown, County Mayo, and on September 26th 1865, a daughter, Anne, was born to Austin Ginnelly and Sibby Lynchehan, in Newport, County Mayo. The first recorded spelling of the family name is shown to be that of Karravy Ginnaly, which was dated January 13th 1683, marriage to Mrs. Christian Smith, at Clones, County Monaghan, during the reign of King Charles 11 of England, known as "The Merry Monarch", 1660 - Surnames became necessary when governments introduced personal taxation. In England this was known as Poll Tax. Throughout the centuries, surnames in every country have continued to "develop" often leading to astonishing variants of the original spelling.1685.