The laws of the time required that an MP who had joined the government had to seek re-election, and the early stages of the campaign saw controversy about whether the election should be contested.

However, the main issue in the election was the Osborne judgment, in which the courts had banned trade unions from imposing a political levy on their members.

[2][3] Provisions of the Regency Act 1707, which remained in force until amended in 1919 and repealed in 1926, provided that MPs appointed as ministers automatically vacated their seats in Parliament.

The Times newspaper noted that the relevant Act had been passed in the reign of Queen Anne "to prevent the Court from swamping the House of Commons with placemen and pensioners", and described the process as "anomalous" and "indefensible" in the 20th century.

[5] There was some uncertainty in the constituency as to the procedure for elections when a seat was vacated during a parliamentary recess, when the writ could not be moved in the Commons in the usual way.

[6] On 14 October, the London Gazette carried the required notice from the Speaker, giving 6 days warning of his intention to issue a writ for the by-election.

He described his first priorities for the campaign as being support for the Osborne judgment,[11] a case brought by a Walthamstow trade unionist which restricted the ability of unions to impose a political levy on their members.

In 1903 he had been the British government's counsel in the Alaska boundary dispute, and he entered the Commons in 1906 at the age of 33, making a strong impression with his speeches.

[14] Tenure in these homes appears to have been short: during the by-election campaign, it was reported that 12,000 of the 39,000 voters had moved house since the electoral register was compiled in July 1909.

He explained that omission in the second paragraph: In January-last, after a long and arduous contest, you for the second time returned me by a large majority to the House of Commons.

Hampden wrote that Simon had made no enemies in the constituency, and that the by-election could have been a chance to thank the MP for his work rather than putting him to the trouble and expense of an election.

He said that his main concern was that "the path to Parliament should be open to men without the distinction of class or income", and that it would not be right for any Liberal government to leave the matter unsettled.

[5] On 12 October, Simon criticised Conservative politicians who claimed to support the entry of working-class people to Parliament, but seemed content that they had the right to enter, without removing the obstacles in their path.

[14] The same day, Johnson responded to criticism of his decision to contest the election, saying that the Osborne judgment was an important matter of domestic politics which had arisen in that constituency, and that as an industrial community they should have a chance of deciding on it.

[14] Walthamstow trade unionists met on 14 October with the local branches of the Independent Labour Party (ILP) and the Social Democratic Federation, to discuss the election.

[8] The delegation from the Trade Union and Socialist Election Committee met Simon on 19 October, after which he wrote to them, explaining that he was not a member of the Cabinet and could not commit the government.

[28] Hundreds of special interest groups organised street-corner meetings, and the suffragists held a procession which included a prisoner on a lorry.

[30] In the end, both candidates agreed that the dominant issue had been tariff reform; but The Times correspondent reported that the campaign had engaged "nobody but the partisan who is always ready for a fight.

The Liberal victory procession that evening was nearly a mile long, as Simon was drawn in an open carriage through the main streets.

[1] Johnson became Mayor of Hackney in 1914, and at the 1918 general election he defeated Simon in the newly created Walthamstow East constituency.