Guinness, Arthur Edward (1840–1915), Baron Ardilaun , businessman, MP, and philanthropist, was born 1 November 1840 at St Anne's, Clontarf, Co. Dublin, eldest son of Sir Benjamin Lee Guinness (qv), 1st baronet and MP, and Elizabeth, third daughter of Edward Guinness of Dublin. He was educated at Eton and TCD, where he graduated BA (1862). After the death of his father (1868) he succeeded as 2nd baronet and, with his younger brother Edward Cecil Guinness (qv) (later Lord Iveagh), became head of the famous brewery founded by his great-grandfather. In the same year he ‘inherited’ his father's Dublin city parliamentary seat, but was unseated for corruption. In 1874 he regained the seat and held it until April 1880, when he was elevated to the peerage as Baron Adilaun of Ashford, Co. Galway. Until 1877 he was an active participant in the business and administration of the brewery, after which he sold his share to his brother. An able businessman, he inherited his grandfather's ability to delegate freely and wisely while retaining control of critical decisions, and during his eight years of partnership with his brother the brewery prospered, with sales more than doubling from just over 350,000 barrels in 1868 to almost 779,000 in 1876.
A staunch tory, he gave generous financial support to the Irish Unionist Alliance, and strongly supported the policy of conservative governments in home and foreign affairs, but made little impact in parliament. He carried on the philanthropic activities of his father, who had been instrumental in funding the restoration of St Patrick's cathedral. He was particularly active in funding projects for the city of Dublin. In 1872, with his brother, he initiated and financed the Dublin Exhibition of Arts and Finance, designed to promote domestic trade and attract visitors to the capital, which succeeded in drawing over 400,000 visitors. As well as providing funding for the completion of the restoration of Marsh's library, begun by his father, he also contributed to the rebuilding of the Coombe Hospital. As president of the Artisans’ Dwellings Company (in which he was a large shareholder), he took particular interest in improving working-class housing conditions, most notably in the areas around St Patrick's cathedral. Perhaps his most notable legacy was financing the transformation of the twenty-two-acre St Stephen's Green into a landscaped garden, which, through an act of parliament sponsored by Guinness, was presented to the Board of Works for the use of Dublin citizens. This generosity was marked by the erection of a bronze statue of him in the park, financed by public subscription in 1891. Another significant purchase of his was the 17,000-acre Muckross estate in Co. Kerry, adjoining the lakes of Killarney, which he bought for £60,000 to prevent the land being exploited by a commercial syndicate, thus enabling it to continue as an important tourist attraction.
As well as being interested in the welfare of TCD, from which he received an honorary LLD, he was also a contributor to the funds of the Church of Ireland and erected at his own cost the Church of All Saints in Raheny, Dublin. Although taking little part in politics in his latter years, he bought two unionist newspapers, the Dublin Daily Express and Dublin Evening Mail, in 1900, two years after he had refused to accept the lieutenancy of Co. Dublin offered to him by the lord lieutenant, Earl Cadogan (qv), at a time when Irish unionists felt betrayed by Lord Salisbury's government. Originally Guinness had resided in a mansion on Leeson St., but his principal Dublin residence was St Anne's, Clontarf, where he entertained lavishly. He also spent time each year on his Galway estate at Ashford, where through road-building and tree-planting (he was a forestry expert) he created considerable employment. He served as president of the RDS (1897–1913) and sponsored the publication of the society's history. In 1871 he married Lady Olivia Charlotte White, daughter of the 3rd earl of Bantry. They had no children, and the Ardilaun barony became extinct after his death in Dublin on 20 January 1915. He was succeeded as 3rd baronet by his nephew Sir Algernon Arthur Guinness (qv).