Dowdall, Thomas Patrick (1872–1942), businessman and politician, was born at Chatham Barracks, Gillingham, Kent, the son of Charles Dowdall, colour sergeant in the 48th foot, and Margaret Dowdall (née Cassidy; d. 1938) of Bandon, Co. Cork. He and his brother James (see below) were educated at the Presentation College, Grand Parade, Cork; together they then visited Denmark, where they studied butter manufacture. Returning to Cork, fluent in Danish and Swedish, the two joined Dowdall Bros, the creamery business of their uncle J. B. Dowdall, which had extensive business contacts in the Baltic countries. Between 1886 and 1888 J. B. Dowdall was instrumental in building or enlarging thirteen creameries and amalgamating them into a consortium known as Anglo-Irish Creameries.
After a short time Thomas took charge of the substantial Irish business, and on the death of their uncle the two Dowdall brothers and their cousin J. B. O'Mahoney formed Dowdall, O'Mahoney & Co. (1905). They soon built up an extensive butter business in Cork, with branches in Manchester, London, and Cardiff; the company also manufactured margarine and soap. A founder member of the Cork Industrial Development Association, T. P. Dowdall was a trustee of the Cork chamber of commerce and vice-president (1939–40) of the Cork incorporated chamber of commerce and shipping. He was also chairman of Dowdall, O'Mahoney & Co. and Cash & Co., and was a director of Ideal Weatherproof and of Dinan Dowdall, wholesale timber merchants of Dublin. First chairman (1938) of the company that owned The Standard, he played a key role in the revival of this catholic newspaper. He was a benevolent and enlightened employer and citizen; his generosity was considerable and largely conferred anonymously.
Dowdall was a keen supporter of the Irish Volunteers and later of Sinn Féin; he endorsed the 1921 treaty and used his influence with others to have it ratified. During the civil war he acted as an intermediary between the warring factions in Cork and became chairman of the Cork Progressive Association. He was honorary treasurer of the Cork city executive of Cumann na nGaedheal, before joining Fianna Fáil with his brother in 1927. In Fianna Fáil he was instrumental in persuading TDs to take their seats in the dáil and was a founding director of the Irish Press; as a TD himself for Cork borough (1932–42), Dowdall rarely spoke in the dáil, but he was a strong advocate of re-afforestation, and outside the chamber he was a co-founder of the Forestry Society and contributed towards the publication of John Mackay's The rape of Ireland (1940). He was also in favour of protectionism and the establishment of a merchant navy.
Unmarried, Thomas Dowdall lived at 4 Alexandra Terrace, St Luke's, Cork. He died 7 April 1942 in Cork, leaving estate valued at £29,213.
Dowdall's younger brother, James Charles Dowdall (1873–1939), businessman and politician, was born 18 February 1873 at Chatham Barracks, Kent. In addition to his partnership in Dowdall, O'Mahoney & Co. (established 1905), he was a founder member and president of the Cork Industrial Development Association; in that role he was instrumental in the establishment of the International Trading Co., which inaugurated direct trade between Ireland and the USA through the Moore McCormack shipping line, which called at Dublin and Belfast. He was chairman of Cash & Co., the Gresham Hotel, the International Trading Corporation, and the Industrial and Life Assurance Amalgamation. He was a director of the Munster and Leinster Bank, the Cork Gas Consumers’ Co., General Textiles, Hawbowline Steel Industries, the Irish National Oil Refineries Co., John O'Neill, the Lucian Cycle Co. and the Irish Press company.
Like his brother a supporter of the treaty, Dowdall was appointed the Irish nominee on the Compensation (Ireland) Commission (otherwise known as the Shaw commission), established to adjudicate on compensation claims arising out of the Anglo–Irish war (1919–21). The commission sat until 1926 and dealt with 41,000 claims, paying out 18,000 awards amounting to £7.4 million. In December 1922 Dowdall accepted a nomination to the Irish Free State senate, where he was an active parliamentarian. In 1927 he joined Fianna Fáil and in 1934 was reelected to the senate, serving until its abolition in 1936, which he opposed. A benevolent supporter of UCC, he was a member of the college's governing body (1919–39) and a senator of the NUI (1923–39). In 1926 he was conferred with an honorary LLD by the NUI.
In 1929 Dowdall married Jane (Jennie) Doggett (Jane Dowdall (qv)) of Dublin. They had one son, Finbarr, and lived at Carrigduv, Blackrock, Cork, and on Merrion Road, Dublin. He died 28 June 1939 at Holyhead, Wales, leaving estate valued at £37,967.