Cornelius B. Nolan was born December 24, 1855, in County Limerick, Ireland. He was educated in Dublin. In the fall of 1873, at seventeen, Nolan immigrated to the United States. Nolan settled in Oswego, New York, where he worked as a day laborer with a railroad section crew, while pursuing his studies at Oswego Academy. In 1877, Nolan moved to Port Allegheny, Pennsylvania, and worked in a tannery for two years. A year later, he went to St. Louis, Missouri, to visit his brother, Thomas. He remained there five years studying law in Roger Foster's law office and at the St. Louis Law School. In 1884, he was admitted to the practice of law in the Missouri courts. After a brief period working as a stenographer for an agricultural house in Chicago, Nolan moved to Montana to become private secretary to the general manager of the freight and passenger service of the Northern Pacific Railroad. However, not long after his arrival in Montana, he resigned his railroad position to become official court reporter for the First Judicial District of Montana, which included Lewis and Clark, Jefferson, and Beaverhead counties. Reporting for Judges N.W. McConnell and Henry L. Blake, Nolan received training which was of great value in his subsequent career. Nolan was elected County Attorney of Lewis and Clark County in 1889. Chosen on the Democratic ticket, he held the position by re-election for five years. In 1896, he was elected Attorney General of Montana. During this four-year term, Nolan took charge of a special grand jury investigation of the alleged bribery of legislators. In 1910, Nolan was elected to the Montana House of Representatives and served one term. While County Attorney, Nolan began to build a private law practice that would eventually become an extensive civil and criminal practice. Initially he worked with John Bean and then, between 1901 and 1904, he was a partner with attorney Albert I. Loeb. In 1906, he formed a partnership with Senator Thomas J. Walsh, which expanded to include William Scallon. In addition to his law work, Nolan invested in mining and real estate, acquiring ranch properties in Broadwater, Park, and Wheatland counties. He was also an active participant in many organizations. He served, with the rank of colonel, on General Toole's staff in the state militia. He also belonged to several fraternal organizations, serving as Masonic Grand Master in 1909. In 1894, Nolan married Harriet Shober. Harriet, niece of Helena attorney John H. Shober, Sr., was a native of Dodge County, Minnesota. During the 1870s and 1880s, she had taught in the public schools of Adair County, Iowa. In 1887, she moved to Helena, Montana, to live with her uncle. After her marriage to Cornelius Nolan, she became active in Helena community projects, Democratic Party politics, and the work of the American Red Cross. Cornelius Nolan died in Butte on June 24, 1922, and his wife Harriet died seven years later, August 23, 1929, at Lake McDonald.