They lived in a large house called Ingleside in the Baltimore County community of Catonsville (which she and her sister sold in 1919 after Bernard Baker's death, and which burned down decades later).

Marguerite adored her father, who built the lucrative Atlantic Transport Line (which he later merged into an entity controlled by financier J.P. Morgan), and often accompanied him on trips to Europe, where she became fluent in French and German.

In June 1901, despite her mother's vehement protestations, Maguerite succeeded in marrying a young stockbroker, Thomas B. Harrison, who lacked inherited wealth and who would die of a brain tumor in 1915.

Harrison concocted many schemes to raise funds for the school, including a charity baseball game and a circus performed by prominent society members.

In 1911, Harrison was named to the board of directors of the Women's Civic League of Baltimore, which advocated for safer and cleaner streets and schools.

Despite having completed only one semester of college, she used her brother-in-law's influence to secure a position as an assistant society editor for The Baltimore Sun at $20 per week.

[6] The November 11, 1918 armistice was declared before she was officially hired, but Harrison was sent to Europe with a new assignment to report on political and economic matters at the forthcoming peace conference.

She arrived in the Soviet Union in 1920 as an Associated Press correspondent and assessed Bolshevik economic strengths and weakness and assisted American political prisoners.

[10] Because of pressure applied by her influential contacts, such as Maryland senator Joseph I. France, she was eventually set free in exchange for food and other aid to the Soviet Union.

[citation needed] Harrison was an important member and sponsor of the production team responsible for the classic ethnographic film Grass (1925).

[13][14] Grass depicts the annual migration of the Bakhtiari, an Iranian tribe who herded their livestock through snow-bound mountain passes under conditions of great hardship to reach high-altitude summer grasslands and then to return to lower elevations for the winter.

[15] As women were excluded from membership in most professional organizations such as the Explorers Club, Harrison participated in the founding of Society of Woman Geographers in 1925.