The opening years of the life of our subject were spent on the other side of the ocean in County Tipperary, Ireland, where he was born in 1833. His father, Patrick O'Donnell, was a native of the same county, and spent his entire life there, dying many years ago. In 1848 most of the family came to the United States, but out subject and his two youngest sisters came in 1849. They lived in New Jersey until 1857, and in the spring of that year Dennis came to this county, of which he has since been a resident, and continuously engaged in farming pursuits.

The industry and perseverance of our subject met with their natural result, and in due time he considered himself justified in establishing a home of his own. He had become acquainted with one of the most estimable young ladies of his township, Miss Elizabeth O'Brien, who became his wife in November, 1856, and they commenced the journey of life together in a manner corresponding with their means and circumstances. A few years of mutual labor made them comparatively independent in the possession of a well-regulated farm, and all the other comforts of life.

Mrs. O'Donnell is the daughter of Patrick O'Brien, a native of Ireland, who spent his last years in Scott County. She was born in Ireland, and by her union with out subject has become the mother of eleven children, ten of whom are living, namely: Maria, James, William, Edward, Lizzie, Frank, Kate, Charlie, John and Thomas. William married Miss Alice Smothers, and remains a resident of this county; Frank is pursuing his studies in the Normal School at Valparaiso, Ind.; the others remain at home with their parents, assisting in the lighter labors of the farm, and attending school.

Mr. O'Donnell is the owner of 668 acres of land all in this county, and divided up into four farms, all being supplied with the necessary buildings. He makes a specialty of graded stock in which industry he has been very successful. He has mixed very little in public affairs, and is no politician or office-seeker. He has a natural affection for the land of his adoption, and is thoroughly in sympathy with her institutions. He usually cases his vote with the Democratic party, and with his family belongs to the Catholic Church.