William English Walling was an American labor reformer and Socialist Republican born into a wealthy family in Louisville, Kentucky. He founded the National Women's Trade Union League in 1903. Moved by his investigation of the Springfield Race Riot of 1908 in the state capital of Illinois, he was among the co-founders of the National Association for the Advancement of Colored People (NAACP) in 1909.

Anna Strunsky Walling was known as an early 20th-century Jewish-American author and advocate of socialism based in San Francisco, California, and New York City. She was primarily a novelist, but also wrote about social problems and the labor movement. Born in the Russian Empire in what is now Belarus, she emigrated as a child with her family to New York City in the United States in 1886. After a few years they moved to San Francisco. Strunsky studied at Stanford University, where she met writer Jack London and later became part of a radical group known as "The Crowd", of which London was also a member. They wrote an epistolary novel together, publishing it anonymously in 1903. She wrote a memoir of him after his early death in 1916.