Eveline Willett Leach was born on 23 April 1849 at Briton Ferry, Glamorgan, Wales, the youngest of 12 daughters of Ann Willett and her husband, Robert Valentine Leach, proprietor of a lunatic asylum. Eveline's father was wealthy and she grew up at Devizes Castle, Wiltshire, England. She became restless, but her father refused to allow her to go out and work. Instead, she was sent to school in France and, after spending time in Germany and Italy, attended Queen's College, London, for three years.
In 1875 Eveline Leach emigrated to Christchurch, New Zealand, where her cousin Samuel Saunders lived. On 8 April 1876 in Riccarton she married Capel Baines, and the couple went to South Australia where Capel worked as a clerk. Two children were born and Eveline experienced poverty for the first time. She was angered by the condition of the poor: their inferior education, ugly surroundings and subjection to crushing social prejudice.
While Eveline and her family were visiting her parents at Devizes Castle in August 1883, Capel Baines died suddenly of a heart attack. Eveline and her children returned to Christchurch, and on 18 December 1884 at Leithfield, she married Herbert James Cunnington, an electrical engineer from Devizes. The couple had two children.
Eveline Cunnington read widely and applied her quick, enquiring mind to the problems of poverty and class. A strong Anglican, in 1891 she became a member of the ladies' committee of the Canterbury Female Refuge, which provided maternity care and moral guidance for unmarried women. The following year she attended the first meeting of the Canterbury Women's Institute, which aimed to emancipate women, and in 1895 she was appointed one of the first two women prison visitors in New Zealand, a position she was to hold for nearly 25 years. She was a founding member of the National Council of Women of New Zealand, attending annual conferences from 1896 to 1898. From 1896 she was associated with the New Zealand Fabian Society, later becoming a founding member of the Canterbury Fabian Society. She wrote Fabian notes for the Lyttelton Times and articles for the Māoriland Worker. Her guiding principle in all these activities was that 'all must share in the good things in life, not only a privileged Few'.
Eveline Cunnington was particularly concerned about the plight of poor girls and women. For their protection, she advocated that the age of consent be raised to 21, or at least 18, and that it should be illegal for girls under 21 to enter brothels. She saw clearly that many were driven to vice: 'get rid of poverty and you will abolish its worst disease – prostitution'. A strong supporter of Josephine Butler in her battle against the double standard embodied in contagious diseases acts in England, Cunnington believed that predatory men should be apprehended and procurers severely punished. She suggested the establishment of a Christian street patrol to warn vulnerable girls and neglectful parents.
Cunnington agitated for prison reform, pointing out that 'From the moment a woman commits a crime, or is supposed to have committed one, she passes into the hands of men'. She advocated that women inspectors be placed in women's prisons and police cells, and pushed for the appointment of women police, doctors, lawyers, jurors and government officials; the education and reform of prisoners; training schools for prison staff; and an aesthetic environment for inmates. When young women offenders were released by the authorities she found clothes and accommodation for them, and sometimes took them into her own home. She wished to give them hope and another chance: 'It is a tragic work, but I do think God will help me in this awful pull with the devil.'
In 1904 Eveline Cunnington departed for a three-year visit to Europe. In England she met with many women whom she admired: Mary Ernest Boole, mathematician and writer; the poor-law guardian, Miss Stansfield; and leading English and American feminists Millicent Garrett Fawcett, Lady Isabella Caroline Somerset and Susan Brownell Anthony. While travelling she became precariously ill, and her brush with death inspired her to dwell on spiritual matters. After her return to Christchurch Cunnington wrote, 'it has been borne in upon me that my last work on earth must be among educated girls.'
In March 1908 she founded the Girls' Social Science Club in Christchurch and began a series of weekly guest lectures and discussions at Deaconess House. Her aim was to reach those privileged girls who had been trained merely 'to be prettily behaved' and instil in them Christian socialist ideals. In 1908 she also gave a series of weekly lectures to 60 senior girls at Helen Gibson's Rangi-ruru school and in April 1910 she established a girls' social science club at Ashburton. Meanwhile, she continued her other community service, heading the poll for the North Canterbury Hospital and Charitable Aid Board the same month.
From 1910 Eveline Cunnington became involved in the education of working people. After listening to a socialist agitator from Australia whom she considered ill-informed, she began to stress the importance of engaging educated speakers to address the workers. In December she was invited by the Iron and Brassmoulders' Union to give a lecture on social purity to a mass meeting of men. This led to attempts to link the church and the socialist movement: in January 1912 Cunnington, Frank Dunnage and others succeeded in arranging a meeting with some of the labour leaders, and each Sunday after church Cunnington went and talked with trade unionists. Tactful and charming, she was rewarded by an invitation from members of the New Zealand Federation of Labour to lecture to them on Sunday evenings. In October she addressed a crowd of about 350 at the Socialists' Hall. Her lecture, illustrated with lantern slides and entitled 'A trip to Hell, with Dante', held the audience spellbound. By November she had given five lectures.
In December 1912 Cunnington went to Wellington to start a girls' club and within two days of her arrival she was asked by the Wellington Wharf Labourers' Union to speak on universal brotherhood to a mass meeting. In 1913 she spoke to the socialists in Christchurch on alcoholism, syphilis and white slavery, and to the Christian Union at Canterbury College on 'Why the working classes will not make friends with the church'. She was the one woman in a group of 10 who formed the Church Socialist League in May of that year, and by June she had preached twice from the pulpit at East Belt Wesleyan Church.
In October 1913, as public controversy over compulsory military training intensified, Eveline Cunnington fell out with many of her socialist, Fabian and Quaker friends over her support for the Defence Act 1909. While this caused her considerable distress, she stuck to her belief that a defence force was necessary. On labour issues, however, she was far from conservative. When organised labour showed willingness to go to arbitration during the waterfront strike of that year, she spoke scornfully of the employers, who refused. In February 1914 she denounced Archbishop Francis Redwood, who had written a pastoral opposing socialism. In a pamphlet entitled The archbishop and socialism, she argued that socialism was the 'economic interpretation of the teaching of Christ'. In March, at a service in the Christchurch cathedral attended by 1,300 men, E. J. (Ted) Howard, general secretary of the Canterbury General Labourers' Union, expressed his gratitude toward Cunnington as one of 'those who had come amongst them to assist by word and deed'.
That year, because of heart problems, Eveline Cunnington was forced to give up lecturing. She summoned L. G. Whitehead, a teacher at Christchurch Boys' High School, and Howard to her house to suggest the formation of a branch of the Workers' Educational Association similar to that in Australia. A proposal was sent to Meredith Atkinson of the University of Sydney asking him to visit New Zealand and spearhead the movement, and on 20 January 1915 a public meeting was held to elect a provisional committee. Leading members of the Christchurch educational establishment and the labour movement were present. Afterwards, Cunnington wrote: 'I had quite an ovation from fifty or sixty men at the meeting.' Cunnington was listed among the 15 members of the committee, which ceased to exist once the WEA was constituted. Most subsequent histories of the WEA do not mention her, but on her death the Christchurch Star was to write that Eveline Cunnington 'was really the founder of the WEA movement in the Dominion'.
From April 1914 Eveline Cunnington had 'quietly been facing the end of this life'. Although she had by now ceased her public activities, she was still sheltering 'prison birds' in her home and writing for the Māoriland Worker. She died at her holiday home at Sumner on 30 July 1916, survived by a son and a daughter from her first marriage and a daughter from her second: Herbert Cunnington had died in October 1915. The large crowd that gathered for her funeral spontaneously sang 'The Red Flag'.