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

During the 19th century thousands of impoverished Irish Families made the long journey to British North America and the United States. These people were leaving a land that had become beset with poverty, lack of opportunity, and hunger. In North America, they hoped to find land, work, and political and religious freedoms. Although the majority of the immigrants that survived the long sea passage did make these discoveries, it was not without much preseverence and hard work: by the mid-19th century land suitable for agriculture was short supply, especially in British North America, in the east; the work available was generally low paying and physically taxing construction or factory work; and the English stereotypes concerning the Irish, although less frequent and vehement, were, nevertheless, present in the land of freedom, liberty, and equality for all men. The largest influx of Irish settlers occurred with Great Potato Famine during the late 1840s. Research into passenger and immigration lists has brought forth evidence of the early members of the O'Malley family in North America: Anthony Mally who settled in Philadelphia in 1854; Michael, William, Anthony, Hugh, John, Patrick, and Thomas Malley, who all arrived in Philadelphia between 1840 and 1860.

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