Consists of an open collection, assembled from multiple sources, of letters and memorabilia of American war correspondent, journalist, and novelist Martha Gellhorn (1908-1998). In addition to authoring numerous works of fiction, many of which were drawn from her reporting, Martha Gellhorn was one of the first female war correspondents during World War II. She accepted her first war assignment in 1937, covering the Spanish Civil War for Collier's Weekly, during which time she began an affair with the American novelist Ernest Hemingway, whom she had met on vacation in Key West, Florida, the previous Christmas. Gellhorn next worked as a foreign correspondent in Czechoslovakia and Finland during the late 1930s and traveled as a journalist along the Burma Road and to China in 1940 and 1941 with Hemingway; they married in 1940. Punctuated by her frequent travels abroad, Gellhorn and Hemingway lived together between their villa, Finca Vigía, in San Francisco de Paula, Cuba, and Sun Valley, Idaho, as Gellhorn continued to work for Collier's as a war correspondent in England, Italy, France, and Germany from 1943 to 1945, reporting on the beach at D-Day, at the liberation of the Dachau concentration camp, and at the Nuremberg trials. After a tumultuous marriage plagued by Hemingway's resentment of Gellhorn's successful career as a journalist and frequent travels, the couple divorced in 1945. In 1949, Gellhorn adopted a son, George Alexander ("Sandy") Gellhorn, from an orphanage in Italy. She went on to cover the Vietnam War and the Arab-Israeli conflict in the 1960s and 1970s and civil unrest in Latin America in the 1980s. She also continued to publish fiction and nonfiction works regularly, spending prolonged stretches of time living and writing in Kenya.

The collection contains fourteen letters from Gellhorn to George Brown, written primarily from Finca Vigía, San Francisco de Paula, Cuba, and Sun Valley, Idaho, during the time Gellhorn was married to Ernest Hemingway in the 1940s. Brown was Gellhorn and Hemingway's personal trainer, tennis partner, and friend, and the letters focus largely on Gellhorn and Hemingway's physical condition, diet, and domestic life. There are also approximately fifty letters from Martha Gellhorn to her adopted son, George "Sandy" Gellhorn, in the late 1960s and early 1970s, written from Kenya, England, Germany, and the United States. Gellhorn's letters to her son are intimate and include her thoughts and reflections on current events, her travels as a war correspondent and journalist, writing projects, family matters, and her complex relationship with her son. A long sequence of letters written from Kenya in 1969 contains a thorough accounting of Gellhorn's experience in Africa, as well as commentary on Hemingway's prose and troubled relationship with his parents. Other materials include a sketch portrait of Martha Gellhorn by Bernard Perlin, circa 1953, and a group of dog tags, pins, and badges from Gellhorn's career as a war correspondent during the Spanish Civil War, World War II, and afterward.