These forty-eight letters written over a ten-year span (1840-1850) from the Prendergast family members in Ireland to those who had come to America document the experiences of both groups.

The letters detail family life: possible emigration for family members still in Ireland; accounts of the health and illness of family members; births, marriages, and deaths; news about extended family and neighbors in Ireland; and inquiries about others who emigrated from County Kerry to the United States. Over one hundred individuals, other than immediate family members, are mentioned in the correspondence.

They also document living conditions in County Kerry during the famine, including mentions of prices of produce, livestock, and rent; details of garden planting, harvest, and weather conditions; and descriptions of the potato blight during the famine years.

The correspondence touches on significant events in County Kerry in the 1840s, including accounts of famine relief efforts by the government, the campaign for Repeal of the Union, and Daniel O'Connell's trial.

The earliest letter in the collection is a letter of reference for Thomas Prendergast from his employer, Dr. Agar, in Ireland, dated April 20, 1840. The remaining letters were written by members of the family in Ireland to their kin in Boston. The final letter in the collection is from Elizabeth in Liverpool as she waits for the Niobe to set sail. It is postmarked September 20, 1850.

The letters were sent to a number of different addresses in Boston, most in the area once known as "Fort Hill," now downtown Boston. The letters authored by James Prendergast were mostly dictated to scriveners, including school teacher Daniel Connell and land surveyor Patrick Mahoney, though James signed his own name and occasionally added a few words.

There is one document that is not a letter. It is one page (and an envelope) and contains notes by an unknown author on Thomas and Jeffrey's naturalization.