This is anglicized form of the Olde Gaelic name O'Leahtlobhair. The Gaelic prefix "O" indicates "male descendant of" plus the personal byname Leathlobhair, a compound of the elements "leath" meaning "half" and "lobar", le pros - a nickname originally given to one of unhealthy constitution. In the modern idiom the name has three spelling variations:- Lawlor, Lalor and Lawler. The prefix "O" has been entirely dropped. The name is widespread in the province of Leinster, especially in Co. Leix or Laois. The Lalors were one of the seven septs of Leix and their territory was located near the Rock of Dunamase in that county. An interesting namebearer was Peter Lalor (1823 - 1889), leader of insurgent gold miners at Eureka, Australia and speaker of the Legislative Council of Victoria. The first recorded spelling of the family name is shown to be that of Harry Lalor of Co. Leix, which was dated 1577, a hero of the Mullaghmast massacre, during the reign of Queen Elizabeth 1, known as Good Queen Bess, 1558 - 1603. 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.