Final answer:
The letter from Samuel Gompers to Judge Peter Grosscup in September 1894 pertains to the Labor rights movement.
Step-by-step explanation:
The letter from Samuel Gompers to Judge Peter Grosscup in September 1894 pertains to the Labor rights movement. Samuel Gompers, the head of the American Federation of Labor (AFL), sought to organize workers and secure better wages and working conditions. His efforts were in response to the labor shortages and the need for peaceful and productive industrial relations during wartime.