Question: The co-founder of the Women's Social and Political Union was arrested for assault and obstruction in what year?

Context paragraphs:
Charlotte Marsh: Charlotte "Charlie" Marsh (1887-1961) was a British suffragette.  In 1907 she joined the Women's Social and Political Union, but did not become active as an organizer until 1908, after completing her training as a sanitary inspector.  In June of that year she was imprisoned in Holloway for a month on charges of obstruction.  The next year she was again imprisoned for heckling Prime Minister Asquith and became one of the first suffragette hunger strikers to be forcibly fed.  During World War I she worked as a mechanic and chauffeur for Lloyd George, whilst continuing her activism.

Edith How-Martyn: Edith How-Martyn, née How (1875, London -1954, Australia) was a British suffragette and a member of the Women's Social and Political Union (WSPU).  She was arrested in 1906 for attempting to make a speech in the House of Commons.  This was one of the first acts of suffragette militancy.

Rachel Barrett: Rachel Barrett (12 November 1874 – 26 August 1953) was a suffragette and newspaper editor born in Carmarthen, Wales.  After attending the University College of Wales in Aberystwyth she became a science teacher.  In 1906 she quit her job after hearing Nellie Martel speak on women's suffrage; she then became a member of the Women's Social and Political Union (WSPU) and moved to London.  In 1907 she became an organiser for the WSPU and after Christabel Pankhurst fled to Paris, Barrett was asked to be the joint organiser of the national WSPU campaign.  In 1912, despite having no journalistic background, she was put in charge of the newly formed newspaper "The Suffragette".  Barrett was arrested on more than one occasion for activities linked to the suffrage movement and between 1913 and 1914 she spent time incognito avoiding re-arrest.

Annie Kenney: Annie Kenney (13 September 1879 – 9 July 1953) was an English working class suffragette who became a leading figure in the Women's Social and Political Union.  She attracted the attention of the press and the public in 1905 when she, and Christabel Pankhurst, were imprisoned for several days for assault and obstruction, after heckling Sir Edward Grey at a Liberal rally in Manchester on the issue of votes for women.  This incident is credited with inaugurating a new phase in the struggle for women's suffrage in the UK, with the adoption of militant tactics.

Women's suffrage in the United Kingdom: Women's suffrage in the United Kingdom was a movement to give women the right to vote.  It finally succeeded through two laws in 1918 and 1928.  It became a national movement in the Victorian era.  Women were not explicitly banned from voting in Great Britain until the 1832 Reform Act and the 1835 Municipal Corporations Act.  Both before and after 1832, establishing women's suffrage on some level was a political topic, although it would not be until 1872 that it would become a national movement with the formation of the National Society for Women's Suffrage and later the more influential National Union of Women's Suffrage Societies (NUWSS).  As well as in England, women's suffrage movements in Wales and other parts of the United Kingdom gained momentum.  The movements shifted sentiments in favour of woman suffrage by 1906.  It was at this point that the militant campaign began with the formation of the Women's Social and Political Union (WSPU).

People's Suffrage Federation: The People's Suffrage Federation was a British Adult Suffrage organisation.  It was created by a merger of the Co-operative Women's Guild and the Women's Labour League in 1909.  Led by Margaret Llewelyn Davies, who was the former Co-operative Women's Guild general secretary.  The group believed that the Women's Suffrage movement was being damaged by class divisions, such as those which resulted in the split between the Women's Social and Political Union and the Women's Freedom League.  They also thought that universal suffrage would be more popular with the liberal Government as it was likely that if only privileged women were granted voting rights, then this would likely aid the conservative vote in future elections.

Christabel Pankhurst: Dame Christabel Harriette Pankhurst, DBE ( ; 22 September 1880 – 13 February 1958), was a British suffragette born in Manchester, England.  A co-founder of the Women's Social and Political Union (WSPU), she directed its militant actions from exile in France from 1912 to 1913.  In 1914 she supported the war against Germany.  After the war she moved to the United States, where she worked as an evangelist for the Second Adventist movement.

Emily Davison: Emily Wilding Davison (11 October 1872 – 8 June 1913) was a suffragette who fought for votes for women in the United Kingdom in the early twentieth century.  A member of the Women's Social and Political Union (WSPU) and a militant fighter for her cause, she was arrested on nine occasions, went on hunger strike seven times and was force fed on forty-nine occasions.  She died after being hit by King George V's horse Anmer at the 1913 Epsom Derby when she walked onto the track during the race.

Liverpool Women's Suffrage Society: The Liverpool Women's Suffrage Society was set up in 1894 by Edith Bright, Lydia Allen Booth and Nessie Stewart-Brown to promote the enfranchisement of women.  The society held its first meeting in a Liverpool temperance hall, with Millicent Fawcett, head of the National Union of Women's Suffrage Societies (NUWSS), as its guest speaker.  The society set up headquarters in Lord Street.  The group became affiliated with the NUWSS in 1898, it held meetings in cafés which included talks, poetry and dance recitals.  Members were recruited from prominent members of society and they distanced themselves from working class suffrage societies such as Women's Social and Political Union (WSPU).

Political union: A political union is a type of state which is composed of or created out of smaller states.  The process is called unification.  Unifications of states that used to be together and are reuniting is referred to as reunification.  Unlike a personal union or real union, the individual states share a central government and the union is recognized internationally as a single political entity.  A political union may also be called a legislative union or state union.

Supporting paragraphs: Annie Kenney Christabel Pankhurst
Answer: 1905