Brown was born in Pittsburgh, Pennsylvania, on 14 June 1913 (claimed 15 June) to Viktor Emanuel Magnuson and Anna Matilda Gustafson. She was the eldest of 10 children, and outlived all her siblings. Her father immigrated to Pittsburgh from Sweden in 1902 to work in the steel mills, and her mother was born in Pittsburgh in 1889, a year after her parents had emigrated from Sweden. She graduated at the top of her class from eighth grade but dropped out of school to assist in raising her younger siblings. Although she did not attend high school, she later earned her GED. Following that, she enrolled in business school and worked as a comptometer (mechanical calculator) operator for several years.

On 28 May 1938, she married Robert Homer “Bob” Brown of Swissvale, a federal air traffic controller. They did not immediately announce the wedding because her employer did not hire married women. The couple had two daughters, Bonnie Lynne and Kristine Roberta. The family lived for many years in the Pittsburgh suburbs. In the city, she worked at G. C. Murphy, a chain of five-and-dime stores.

In 1962, the Pittsburgh Air Traffic Control Center was relocated to Oberlin, Ohio, and the following year, the family moved there. Her husband retired in 1973. They were active members of the First Church of Oberlin. In her later life, she enjoyed playing bridge, gardening, berry picking, knitting, and volunteering at the polls.

Her first language was Swedish, and she was proud of her heritage. She visited Sweden three times (the last time at the age of 88) and often recited a grace prayer in Swedish that she had learned in her childhood. Following her husband’s death in 1990, she moved to Texas to live with her daughter Kristine, who died in 2015. Brown, then aged 102, moved to a retirement facility in Nashua, New Hampshire, to be closer to her daughter Bonnie, who resided in Massachusetts.

Brown claimed taking cod liver oil daily as a secret to her longevity. Her hearing had deteriorated by her 109th birthday, but was reported to be in perfect health otherwise. At some point, she participated in the New England Supercentenarian Study at Boston University.

Brown passed away at Langdon Place Of Nashua senior living community in Nashua, New Hampshire, USA, on 5 December 2023, at the age of 110 years, 174 days. She was survived by her daughter Bonnie, five grandchildren, and eight great-grandchildren.