Leach was born in Illingworth, near Halifax, but moved to the town and grew up in a slum called Ratten Row, where his mother died when he was five.

Moving to Elland near Halifax he built up a successful boot and shoe business, by 1871 employing three men, one woman and two boys.

[6] In Birmingham he began his Sunday afternoon lectures which were so popular that after a couple of years he was forced to use the Town Hall as the numbers had become so great.

[8] After four years at Ladywood the Methodist New Connexion wanted to send him to London, but a committee was set up to use the redundant Highbury chapel in Graham Street and he was invited to be the pastor and hence he became an Independent or Congregational minister.

However, in 1886, when Joseph Chamberlain split the party he sided with Gladstone which left him in a difficult position in Liberal Unionist dominated Birmingham.

[12] In 1888, Leach, who was living in Brondesbury Road, Kilburn, stood as a Progressive candidate in Chelsea division for the London School Board.

In Manchester he was much involved with Passive Resistance, the movement protesting about the Education Act 1902 and the requirement for ratepayers to support Anglican and Catholic schools.

As an adjunct to his work within the temperance movement he was one of the founding directors of the Abstainers and General Insurance Company[22] and later became its Vice Chairman.

[24] He had not been so fortunate in his private life, and he lost his two sons, Herbert and Harry, in infancy, and two of his four daughters, Ada and Dora, to TB, both at the age of 24.

[26] He was described by The Times as a weak candidate, but one who stood to inherit the strong Colne Valley Liberal vote,[27] and at the January 1910 general election, he defeated the Independent MP Victor Grayson.

In February 1911 he introduced his private members Trade Union Bill [31] to try to overcome the problems caused by the Osborne judgment, but it was to disappear into the parliamentary timetable.

Leach continued to preach occasionally while a Member of Parliament; he also travelled widely including to the near East, Canada and the United States.

[32] Appointed as a Chaplain to the Armed Forces, 4th class, during the First World War (at outbreak of which he was 67 years old), his duty was to visit the wounded in the London Military Hospitals.