Emily Patricia Ray was born in Dublin, Ireland, probably in 1863 or 1864, the daughter of Anna Thompson and her husband, Edmund Ray, a barrister. She trained as a compositor and proof-reader in Blackrock, Dublin. After 12 years in London working as a compositor on a Fleet Street newspaper, Emily, together with her widowed sister Clementina Kirkby and her two nieces, emigrated to New Zealand. They arrived in Wellington on the Tongariro in June 1891, and spent a month in Wellington before moving to Auckland where Emily spent the rest of her life. She was married there on 7 August 1894 to William Edward Gibson, an asylum attendant and later a bricklayer. Until the first of her three children was born she worked as a proof-reader at the Auckland Star.
She had been involved in the women's suffrage movement in London, and on her arrival in Auckland Emily 'naturally' continued the struggle there and joined the Auckland branch of the Women's Franchise League. In November 1893 she went with a group of women to vote for the first time at the Army Hall in the centre of Auckland and walked between two rows of jeering men: 'We were brave because we were together but not one of us was not trembling and trying to hold back tears.' Gibson considered herself a Liberal, and not long after that election she and some other women decided that the league (re-established as the Auckland Women's Political League in January 1894) was too conservative and formed the Auckland Women's Liberal League, 'supporting the Government in every way possible'. The group met in the evening to encourage working women to attend and campaigned vigorously to get a compulsory half-day holiday for shop assistants and domestic workers. The poor working conditions of domestic servants was a subject close to Gibson's heart and she delivered a paper on the subject to the annual conference of the National Council of Women of New Zealand held in Auckland in 1899.
In 1907 Emily Gibson and her sister revived the Auckland Women's Political League, which had gone into recess two years before. Emily served as secretary (1907–13 and 1914–17), giving evidence in that capacity to the Royal Commission on Cost of Living in New Zealand in 1912. With the Liberal party in decline she became a member of the New Zealand Labour Party when it was formed in 1916, believing this to be the best means to achieve her social and humanitarian goals. She was also a founding member of what was to become the New Zealand Section of the Women's International League for Peace and Freedom (WILPF), established in Auckland in 1916. In 1925 it became the Auckland women's branch of the Labour Party and it was through the efforts of Emily Gibson, who was corresponding secretary until 1930, that it kept in contact with the international body in Geneva.
After the WILPF split from the Labour Party in 1930, Emily Gibson resigned from the women's branch but had rejoined by 1935 when her daughter Ray Wynn was elected president. When Woman To-day, a monthly magazine for women, began publication in 1937, Emily was a member of its advisory board, a position she kept until the magazine folded in October 1939. She contributed articles to Woman To-day as well as to the labour newspaper Maoriland Worker, mostly on issues concerning women, and also published poems. Her involvement with the New Zealand Section of the WILPF continued, despite its dwindling numbers, until it finally stopped functioning in 1946.
Emily came to call herself a socialist, but despite her lengthy involvement with the WILPF she was not a pacifist, believing that there was such a thing as a just war. She also believed strongly in the League of Nations and is perhaps best considered an internationalist. Eleven years after her husband's death Emily Gibson died in Auckland on 24 April 1947. She was survived by two daughters and a son. A tiny, gentle, yet fiery and determined woman, her life was spent working for the causes of peace and social justice.