Carroll, Donal Shemus Allingham (‘Don’) (1928–2000), tobacco manufacturer and banker, was born 26 December 1928 in Cork, only son of John Donal Carroll, Cork county medical officer, and Sheila Maureen Carroll (née Flynn), daughter of Joseph John Flynn of Leeson St., Dublin. He had one sister. After his father's death his mother remarried; her surname became Maunsell.
He was educated at the Dominican college, Wicklow, and Glenstal Priory School, Murroe, Co. Limerick. On leaving school, when he applied to join the firm founded by his great grandfather, P. J. Carroll (qv), his uncle, James Marmion Gilmor Carroll (qv), instructed him to obtain a qualification and then reapply. He read economics at TCD but later left to become an articled clerk (1947–52) with Stokes Bros & Pim. Qualifying as a chartered accountant in 1952, he once again applied to the family firm and was successfully interviewed by two non-family directors. As factory superintendent he quickly realised that production was erratic, industrial relations were poor, and quality was bad. He persuaded his uncles to bring in Associated Industrial Consultants, with whom he worked on improving the management of the factory for the next two years. By 1955 he had helped to improve quality, match production to demand, and increase sales.
As sales increased it became clear that additional capital was required to finance future growth. The Bank of Ireland initially refused a request for the money but reversed the decision as a result of a second meeting with Carroll, and were so impressed that they asked him to become a director the following month (April 1956); later that year he became a director of the family business. In 1957 he became joint managing director of P. J. Carroll and Co. Ltd with his uncle Walter John Carroll, the year the company launched its first filter-tip cigarette and soon-to-be-famous brand Carroll's no. 1. Within two years the company had captured 20 per cent of the Irish market. In 1960 he became sole managing director and chairman of P. J. Carroll & Co. Ltd and formed an alliance with Carreras Ltd (later (1972) Rothmans International). Carreras injected capital into the family firm through the purchase of 40 per cent of the equity. This provided the company with the rights to produce Rothmans in Ireland and enabled him to continue his expansion plans, placing a greater emphasis on targeting specific markets; a marketing headquarters was established in Dublin.
As deputy governor of the Bank of Ireland (1962–4) he identified problems that had to be addressed, in particular the Bank of Ireland's position as banker to the Irish government while its reserves were kept in London. The bank could not, therefore, meet the borrowing requirements of the government. When he became governor (1964) it was decided that he would serve a longer term than usual to allow for strategic planning and action on the future of banking in Ireland. As chairman of the Irish Banks Standing Committee he brought in the American consultancy firm McKinsey to assess the state of Irish banking. The McKinsey report found that Ireland needed fewer and larger banks, and advised the banks to develop merchant banking facilities. For his part Carroll oversaw the merger of the Bank of Ireland with the National Bank and the formation of the Investment Bank of Ireland.
The problem of government borrowing remained and was exacerbated by the sterling crisis and the subsequent rules imposed on sterling reserves by the Basle agreement. As chairman of the Irish Banks Standing Committee, Carroll and T. K. Whitaker, secretary of the Department of Finance, worked out a formula for transferring control of the external reserves of the Irish banks from London to the Central Bank in Dublin. This meant that the Irish Central Bank became a central bank in the proper meaning of the term for the first time. Carroll decided that this also provided an opportunity to end the ambiguous position of the Bank of Ireland as both banker to the government and a private bank, advising the government to transfer its business to the Central Bank, of which he subsequently became a director (1971). That same year he was appointed chairman of Lloyd's & Bolsa International Bank Ltd, based in London. The joint venture soon encountered problems and he advised Lloyd's to buy out their partners, with him moving to the position of deputy chairman of Lloyd's Bank. The proposal was accepted but the bank opted for an establishment figure as deputy chairman so he returned to Dublin in 1973. In 1982 he once again became governor (1982–5) of the Bank of Ireland, but the bleak economic circumstances of the 1980s prevented his having an impact similar to that of his previous term.
By the time he had stepped down as governor of the Bank of Ireland in 1970, P. J. Carroll & Co. Ltd had taken 50 per cent of the Irish cigarette market and constructed a new factory at Dundalk. In 1971 he became deputy chairman of Carreras Ltd. He resumed the role of chairman (1973) at P. J. Carroll & Co. Ltd at a time when cigarette sales were declining, and therefore embarked on a number of unsuccessful attempts to diversify during the 1970s. In 1985 he once again returned to P. J. Carroll and Co. Ltd, where he became both chairman and managing director (1985–90). His attempts at diversification into areas such as marketing, venture capital, and fish farming (1986) were more successful than in the 1970s. He retired from the firm in 1990.
In addition to his careers in banking and tobacco he was a director of Dunlop Holdings Ltd, Irish Ropes Ltd, and United Distillers of Ireland Ltd (later Irish Distillers Ltd). He was also governor (1974–80) of the Irish Times Trust Ltd, as well as a council member of the Institute of Chartered Accountants in Ireland (1967–71), the Irish Management Institute (1968–71), and the Confederation of Irish Industry (1969–71). In 1977 he was president of An Taisce and the following year he helped to found Co-operation North, a non-political organisation designed to foster cross-border cooperation and understanding. In 1969 Dublin University conferred on him an hon. LLD. He died 13 September 2000 in Dublin. He married Monica Doreen Mary, daughter of Lt-col. Stanislaus Ewen Francis Moran of Dún Laoghaire, Co. Dublin. They had one son and one daughter and lived at Beechgrove, Loughlinstown, Co. Dublin.