Mitchell engaged in contentious negotiations with mining companies, including one in which President Theodore Roosevelt had to intervene, resulting in an eight-hour workday and a minimum wage.

[citation needed] When his successor, Thomas Lewis, won approval of a resolution forcing UMWA members to resign from the National Civic Federation, Mitchell left the union.

John Mitchell died age 49 on September 9, 1919, from pneumonia[3] in New York City and was buried in Cathedral Cemetery in Scranton.

[4] A portion of his ashes, along with an engraved urn, were donated to the United Mine Workers of America, International Office.

A statue of Mitchell stands on the grounds of the Lackawanna County Courthouse, Scranton, Pennsylvania, the site of the Coal Strike of 1902 negotiations in which President Roosevelt participated.