First found in county Tyrone, where they held a family seat from ancient times.

To escape the religious and political discrimination they experienced primarily at the hands of the English, thousands of Irish left their homeland in the 19th century. These migrants typically settled in communities throughout the East Coast of North America, but also joined the wagon trains moving out to the Midwest. Ironically, when the American War of Independence began, many Irish settlers took the side of England, and at the war's conclusion moved north to Canada. These United Empire Loyalists, were granted land along the St. Lawrence River and the Niagara Peninsula. Other Irish immigrants settled in Newfoundland, the Ottawa Valley, New Brunswick and Nova Scotia. The greatest influx of Irish immigrants, however, came to North America during the Great Potato Famine of the late 1840s. Thousands left Ireland at this time for North America and Australia. Many of those numbers, however, did not live through the long sea passage. These Irish settlers to North America were immediately put to work building railroads, coal mines, bridges, and canals. Irish settlers made an inestimable contribution to the building of the New World. Early North American immigration records have revealed a number of people bearing the Irish name O'Neil or a variant listed above, including: Captain James Neale (1615-1684) who arrived about 1635 in Maryland and received 1,000 acres of land, many of his descendants became Jesuit priests; Edward Neal settled in Boston in 1849.

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