In 1906 he was elected as a Progressive (Liberal) to Battersea Borough Council for Latchmere ward; at the same time, West Indian Henry Sylvester Williams won in Marylebone.

Archer successfully campaigned for a minimum wage of 32 shillings a week for council workers but lost his seat in 1909; he was re-elected in 1912.

He won by 40 votes to 39 among his fellow councillors, and gave a notable victory speech: His success was reported in the US journal The Crisis in January 1914.

He convinced the Labour Party to endorse Saklatvala, who was duly elected – one of the first Indian MPs in Britain.

Archer served as a governor of Battersea Polytechnic, president of the Nine Elms Swimming Club, chair of the Whitley Council Staff Committee, and a member of the Wandsworth Board of Guardians.

In 2004, John Archer was chosen for the "100 Great Black Britons" list,[8] coming 72nd in a public vote.

[9] In April 2013 Archer was one of six people selected by Royal Mail for the "Great Britons" commemorative postage stamp issue.

[10] In November 2013 Archer was honoured by English Heritage with a blue plaque at his former home, 55 Brynmaer Road, Battersea.