Thomas McCullough was born in County Tyrone in the northern part of Ireland in 1826. He learned the tailor's trade in Glasgow , Scotland, and at the age of twenty-one came to America and settled first in New York City, where he found employment in the tailoring establishment of P. L. Cone of that city. In 1857 Mr. Cone came to Davenport, Iowa, and brought Mr. McCullough with him. He remained in the employ of Mr. Cone in the capacity of cutter until 1868, when he began business on his own responsibility at 148 West Third Street, shortly after which he removed to 224 Brady Street and finally settled at 318 Brady Street, where he remained in business until his death in 1880 at the age of fifty-four years.
Mr. McCullough was a man possessed of rare business and mechanical ability. He was an ardent worker in promoting Irish immigration, in assisting his countrymen to come to the United States, in securing for them employment, and doing similar acts of kindness.
He was always an active member of the Roman Catholic Church, and believing the Democratic party to be more liberal in its views than rival political organizations he always cast his vote accordingly.
In 1854 he was united in marriage to Miss Elizabeth H., daughter of Jerome and Mary H. Dorney, natives of Ireland. Two children were born of this union: William J. and Francis J. McCullough. Mrs. Thomas (Dorney) McCullough was a woman of whom special mention should be made in a work of this character. She was a woman endowed with remarkable energy, and under all circumstances had the courage of her convictions. She was associated with Mrs. Dr. Peck and other ladies on the Davenport library board, and was also one of the nine trustees selected by Mrs. Clarissa Cook for the Davenport library, being the only lady selected in fifteen years. She held the office of treasurer of the Davenport Library Association for a number of years, and devoted a great part of her life to Catholic Church work. She organized the first Catholic Union Society in Davenport and was its first president, and also represented that society on the board of the associated charities of the city.