Born in Caven, Ireland in 1875, McManus immigrated to Australia and was the organizer of the Australian Workers' Union from 1900 to 1905.

During the factional bickering amongst the early Labour movement in New Zealand, McManus sided with Paul and David McLaren.

[3] Had an Independent Liberal or Reform Party candidate also contested and forced a second ballot, McManus may well have been elected to Parliament.

[4] The SDP was strongly opposed by Paul, though the pair remained on speaking terms with one another.

[1] He attempted a political comeback in 1938 standing for the Dunedin City Council again, but was unsuccessful.