Career
She is described by the Dictionary of New Zealand Biography as "New Zealand"s pioneer suffragist". Her first husband is known to have been dead by this point. In 1864, she met British women"s rights advocate Maria Rye, who was visiting New Zealand.
Müller began to closely follow feminist movements in Britain and the United States.
In 1869, still under a pseudonym, she wrote An appeal to the men of New Zealand, the first pamphlet on the issue of women"s suffrage ever to be published in New Zealand. Müller"s argument was that it was necessary for women to obtain the vote in order for them to contribute fully to the progress of the nation.
According to the Encyclopedia of New Zealand (1966), her pamphlet "created considerable interest both in New Zealand and abroad". She received a letter of support and congratulations from John Stuart Mill.
Unwilling, because of her husband"s position, to become a public activist, Müller nonetheless met William Fox in private to discuss her views.
According to the Brooklyn Museum, "the Married Women"s Property Acting of 1870 incorporated many of her ideas". She revealed her identity only in 1898, seven years after her husband"s death.