Charles James Patrick Mahon, Irish nationalist journalist, barrister, parliamentarian and international mercenary, is born into a prominent Roman Catholic family in Ennis, County Clare, on March 17, 1800.

Mahon, the eldest of four children, is the son of Patrick Mahon of New Park, who took part in the Irish Rebellion of 1798, and Barbara, a considerable heiress and the only daughter of James O’Gorman of Ennis. He studies at Clongowes Wood College, where he is one of the earliest pupils, and at Trinity College Dublin, where he takes his BA in 1822 and his MA in law in 1832. Following his father’s death in 1821, he inherits half the family property and becomes a magistrate for Clare.

In 1830, Mahon marries Christina, the daughter of John O’Brien of Dublin. She is an heiress and has property valued at £60,000 in her own right, which gives him the resources to seek election to parliament. The couple spends little time together, and she dies apart from him in Paris in 1877. They have one son who dies in 1883.

In 1826, Mahon joins the newly formed Catholic Association. He encourages fellow member Daniel O’Connell to stand for election at the 1828 Clare by-election. O’Connell’s election, in which Mahon plays a large role, persuades the British Government to pass the Roman Catholic Relief Act 1829, which finalises the process of Catholic Emancipation and permitted Roman Catholics to sit in the British Parliament.

As a result, when Mahon is elected for Clare at the 1830 United Kingdom general election, he is entitled to take his seat. However, during the election campaign he quarrels with O’Connell, and after his election he is unseated for bribery. He is subsequently acquitted, and stands again at the 1831 United Kingdom general election, but is defeated by two O’Connell-backed candidates, one of whom is his old schoolfriend Maurice O’Connell, Daniel O’Connell’s son. He gives up on politics, becomes deputy lieutenant of Clare, and captain of the local militia.

Mahon becomes a barrister in 1834, but the following year, he leaves for Paris. There he associates with Charles Maurice de Talleyrand-Périgord, becoming a favourite at Louis Philippe‘s court and working as a journalist. He travels the world, spending time in both Africa, where he befriends Ferdinand de Lesseps, engineer of the Suez Canal, and South America, before returning to Ireland in 1846.

At the 1847 United Kingdom general election, Mahon is elected for Ennis, and declares himself a Whig in favour of Irish Repeal. However, he opposes the Young Irelanders, and narrowly loses his seat at the 1852 United Kingdom general election.

Following his defeat in the 1852 election, Mahon returns to Paris, then travels on to Saint Petersburg, where he serves in the Imperial Bodyguard. During this period, he journeys through lands from Finland to Siberia. He then travels across China, India and Arabia. His finances largely exhausted, he serves as a mercenary in the Ottoman and Austrian armies before returning to England in 1858. Late that year, he leaves for South America, where he attempts to finance the construction of a canal through Central America.

After exploits abroad Mahon returns to Ireland in 1871 and is a founding member of the Home Rule League. Nearly ruined by his ventures, he even ends up at the Old Bailey as a consequence of his dealings, but is acquitted. He is defeated in Ennis at the 1874 United Kingdom general election, and also at the 1877 Clare by-election. Finally, he wins the 1879 Clare by-election and holds the seat at the 1880 United Kingdom general election.

Mahon is a close associate of Charles Stewart Parnell, who he successfully nominates for the leadership of the League in 1880, but is dropped in 1885 as a party candidate because of his age and his tendency to vote with the Liberal Party in Parliament. He is also embroiled in a court case disputing the will of his son.

Parnell personally ensures Mahon is a candidate at the 1887 County Carlow by-election, which he wins at the age of 87 as a Liberal. By this point, he is the oldest MP in the House of Commons of the United Kingdom. He dies at his home in South Kensington, London on June 15, 1891 while still in office.

Mahon had served alongside William O’Shea as an MP, and the two were close friends. He introduced him and Katharine O’Shea, his wife, to Parnell. After Parnell is named in the O’Sheas’ divorce case in 1890, Mahon splits with Parnell, siding with the Irish National Federation. However, Parnell attends Mahon’s funeral in Glasnevin Cemetery a few months later.

(Pictured: Caricature of James Patrick Mahon by Sir Leslie Matthew Ward under the pseudonym “Spy” published in Vanity Fair in 1885)