His first wife was Mary Edith Scott (Mabel). They married in 1890, and Mabel tried to divorce him (and lost) in 1891; she sued for restoration of conjugal rights in 1894. The earl requested a judicial separation in 1895, but she appealed and it was overturned. His mother-in-law also tried to harass him and was convicted for libel in 1897. Mabel, Countess Russell made her living by singing on the variety stage even while she was married to Frank Russell.
Russell next married Marion Cooke Somerville (b. abt. 1857-1858), the twice-divorced daughter of an Irish master shoemaker, in the United States in 1900, after establishing domicile in that country and obtaining a divorce in Nevada. The British authorities considered such a divorce invalid, and Lord Russell was arrested and was convicted of bigamy in the House of Lords on 18 July, 1901. He was sentenced to only three months in prison, on account of the "extreme torture" he had suffered in his first marriage. The first Countess Russell had already obtained a divorce, and he married Mrs Somerville on 31 October, 1901, three days after it became absolute. His second wife divorced him in 1915, after obtaining an annual income for life, suggesting some collusion.
Russell married thirdly the novelist Elizabeth von Arnim (nee Mary Annette Beauchamp), widow of Count Henning August von Arnim-Schlagenthin (d. 1910), the next year. Von Arnim, who had a three-year affair with H.G. Wells, ended her relationship with him when his other lover Rebecca West became pregnant. She became involved with Russell in 1914, and married Russell on 11 February 1916. The marriage failed quickly and acrimoniously, and the couple separated in 1919, or immediately (according to other sources). However, they never divorced. At the start of the Second World War, Von Arnim moved to the United States where she died.
Earl Russell had no children, but his second and third marriages brought him several stepchildren. His second wife Marion had one son by her first husband and two sons by her second husband. His third wife Elizabeth had five children by her first husband.
Ottaway (2007) comments that:"In the early days before personalised number plates, the focus was on number plates such as A1. That particular number plate was sold by London county council in 1903 to the second Earl Russell, who queued for the entire night outside the council offices to have the right to be able to buy it. He beat someone else to it by just five seconds. Having acquired it, he sold it to the chairman of the London county council four years later, in 1907. History does not relate whether he made a profit."
As Under-Secretary of State for Transport, he introduced the highway code and abolished speed limits. He went on to become Secretary of State for India. The Ramsay MacDonald Government later reintroduced speed limits, but waited until the second Earl Russell had died on 3 March 1931.
During his life, Russell spoke for reform of the divorce laws, but his efforts to obtain such reforms starting in 1902 were partly negated by his own personal history.
Rupert Furneux. Tried by their Peers. Cassell, London, 1959. Two chapters are devoted to trials for bigamy, that of Elizabeth Chudleigh, Duchess of Kingston and that of the 2nd Earl Russell.
Ian Watson. " Mollie, Countess Russell", Russell: the Journal of Bertrand Russell Studies 23 (2003): 65-68.