Her mother, Emma Alma Matters (née Warburton), gave birth to five daughters and five sons, with Muriel being the third oldest child.

In 1894, under legislation passed by the Kingston Government, the colony had gained attention for being the first self-governing territory to enfranchise women on the same terms as were granted to men.

[3] At the time of the federation of Australia in 1901, Matters had returned to Adelaide and taught elocution,[4] while concurrently performing for audiences at numerous halls and salons across the state.

Matters eventually performed at the home of Kropotkin and, after her recital, he challenged her to use her skills for something more useful stating that, "Art is not an end of life, but a means.

"[7] The WFL was led by Charlotte Despard and was set up to be more democratic than the Pankhurst-led Women's Social and Political Union (WSPU) suffragettes.

Despite the occasional heckler, Matters and the others involved, such as Charlotte Despard and Amy Hicks, were successful in achieving those aims and established several branches.

The purpose was to raise attention to the struggle of women and to remove the "grille", a piece of ironwork placed in the Ladies' Gallery that obscured their view of parliamentary proceedings.

[2] She and an associate, Helen Fox, both chained themselves to the grille of the Ladies' Gallery and Matters began loudly proclaiming the benefits of enfranchisement directly to the elected MPs.

[citation needed] Although not noted in Hansard, the official record of proceedings in the House of Commons, Matters' pronouncements were, technically, the first speech by a woman in the British Parliament.

[11] Meanwhile, Violet Tillard lowered a proclamation to the politicians below using pieces of string, and a man from the Stranger's Gallery threw handbills onto the floor of Parliament.

Not charged over the incident, Matters and the other women involved were soon released near St Stephen's Entrance, where they rejoined other members of the WFL who were still protesting.

Matters was found guilty of wilfully obstructing London Police and was sentenced to one month imprisonment to be served at Holloway Gaol.

To gain attention and to promote the suffrage cause, Matters decided to hire a small dirigible (airship) owned by Percival G. Spencer, intending to shower the King and the Houses of Parliament with WFL pamphlets.

Instead, Matters, beginning at Hendon airfields, hugged the outskirts of London flying over Wormwood Scrubs, Kensington, Tooting and finally landing in Coulsdon with the trip lasting an hour and a half in total.

Matters scattered 56 pounds (25 kg) of handbills promoting the WFL's cause and leading members of the league, Edith How-Martyn and Elsie Craig, pursued her by car.

[21] Accompanied by Violet Tillard on the tour, Matters presented the audience with illustrations related to the movement and donned a facsimile of her prison dress.

[22] At the conclusion of the lecture tour, Matters helped Vida Goldstein secure an Australian Senate resolution that outlined the country's positive experiences with women's suffrage.

Within a year of Matters' return from her native country, she became involved with the "Mothers Arms" project in East London led by Sylvia Pankhurst.

[25] A letter from Matters in The Scotsman, published in April, denounced forcible feeding and the Cat and Mouse Act, which were being imposed on suffragettes.

"[33]: 5  Furthermore, she provided a rebuttal of the militaristic arguments presented in the book War and the World's Life by Colonel Frederic Natusch Maude[dead link‍].

[34] Spain's neutrality during the Great War allowed Matters to go there to study the child-centred approach to learning taught by Montessori, which fitted her view that education should be a universal right.

[34] In 1922, Matters undertook a second lecture tour of Australia but this time her primary concern was to advocate Montessori's ideas to the educators of her native country.

In her later years, Matters often wrote letters to the editor of newspapers, frequented the local library and was heavily involved in the Hastings community.