Blanche Marie Louise Oelrichs was born in Newport, Rhode Island, to Charles May Oelrichs and Blanche de Loosey, the youngest of four children. The family spent summers in Newport, Rhode Island amidst the Astors, the Vanderbilts, and numerous other wealthy elites of American society during the Gilded Age.
Blanche Oelrichs, bisexual, was an involved activist for women's suffrage and a writer. French portrait artist Paul Helleu described Strange as the "most beautiful woman in America."
In 1910, Oelrichs married her first husband Leonard Moorhead Thomas, with whom she had two children. Blanche Oelrichs developed a "literary urge" in 1914 when she began creating works of poetry and theatrical plays.Oelrichs first used the androgynous Nom de plume of Michael Strange to publish her poetry in order to distance her Society reputation from its sometimes erotic content, but it soon became the name under which she presented herself for the remainder of her life.
Her first collection of poems was published in 1916 under the pen name Michael Strange. Her interests caused a rift with her husband and they divorced in 1919.
Through her social activities, Strange met renowned actor John Barrymore. Blanche continued seeing him for four years; and, after divorcing Thomas, she married Barrymore on August 5, 1920. She was already several months' pregnant with their only child.
With drawings provided by John Barrymore, Blanche published a book in 1921 titled Resurrecting Life . Her pseudonym was intended to separate her Society family from the erotic content of the volume and its connection to her affair from Barrymore, but instead the vast popularity of the volume led to greater fame and notoriety, and her adaptation of "Michael Strange" name permanently.
She then turned her writing skills to the creation of theatrical plays including a 1921 Broadway production titled Clair de lune . In 1921, Strange was among the first to join the Lucy Stone League, an organization that fought for women to preserve their maiden names after marriage.
Blanche spent a great deal of time in Paris, France during the next few years while her husband performed abroad. After returning to live in New York, she began acting in live theatre. Her marriage to John Barrymore ended in May 1925. She then joined a summer stock company in Salem, Massachusetts and appeared in two Broadway plays in 1926 and 1927.
Another book of Blanche's poetry was published in 1928 under the title "Selected poems, by Michael Strange " and the following year she married a third time to the prominent New York attorney Harrison Tweed. During the second half of the 1930s Blanche hosted a poetry and music program on New York radio station WOR that gained a strong audience. In 1940, She published her autobiography, Who Tells Me True . In 1942 she and Harrison Tweed divorced.
Starting in the summer of 1940 until her death, Blanche was in a long-term relationship with Margaret Wise Brown, the author of many children's books. The relationship began as something of a mentoring one, but became a romantic relationship and they lived together at 10 Gracie Square beginning in 1943.
Blanche died from leukemia in Boston, aged 60. Margaret Wise Brown was made her literary executor. Upon her death two years later, Michael Strange's papers were delivered to Brown's sister Roberta who contacted Diana Barrymore who instructed her to burn them.