Born as Mary Amelia Foster, she studied at the Bedford Ladies College, London.
She lived for a time in Paris, where she became a socialist and trade unionist, but later returned to London.
There, she joined the Independent Labour Party and took a prominent role in campaigning in the 1897 Barnsley by-election.
She also became the London representative of the Labour Leader, and contributed to the Railway Review under the pseudonym "Margery Daw".
[2] Macpherson wrote to Ramsay Macdonald, proposing this, and after initial resistance, it was founded as the Women's Labour League.