First found in Connemara, County Galway in Connacht where they held a family seat from very ancient times.

The English-ruled Ireland of the late 18th and 19th centuries featured a rapidly increasing population and an agricultural-based economy. This combination proved to be disastrous in the 1840s after a couple of failed potato harvests. Thousands died of disease and starvation, and thousands more left the country, often bound for North America. Those that survived the journey to North America were put to work building the bridges, canals, roadways, and railways needed for the development of an industrial society. Those Irish, although often despised by those already established in North American cities and towns, played an instrumental role in making Canada and the United States the powerful and wealthy nations that they are today. An examination of early immigration and passenger lists has shown many immigrants bearing the name O'Flaherty: James Flaherty who landed in Virginia in 1651; followed James Flaharty in 1651; Timothy Flaharty settled in Boston Massachusetts in 1767; Ann Flaherty settled in New York in 1850.

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