First found in county Galway, where they had been granted lands by Strongbow after the Norman invasion of Ireland in 1172, and became one of the "Tribes of Galway.".

Death and immigration greatly reduced Ireland's population in the 19th century. For the native Irish people poverty, hunger, and racial prejudice was common. Therefore, thousands left their homeland to seek opportunity in North America. Those who survived the journey and the quarantine camps to which they arrived, were instrumental towards building the strong developing nations of the United States and the future Canada. By far, the largest influx of Irish settlers occurred with Great Potato Famine during the late 1840s. These were employed as construction or factory workers. An examination of passenger and immigration lists has shown early immigrants bearing the name Kilmartin: Daniel and Pat Gilmartin who arrived in New York State in 1803; Francis Gilmartin settled in New York State in 1795; Pat Gilmartine settled in New York in 1854..

Motto Translated: My help is from the Lord.

For more information on the last name Kilmartin, the PDF Surname History is available for purchase as well as other products.