The prominent document that criticized the injustices against the working class during the Industrial Revolution is "The Condition of the Working Class in England" by Friedrich Engels, published in 1845. This influential work provided a critical analysis of the social and economic conditions faced by the working class during the rapid industrialization of England. Engels documented the harsh realities of labor, including long hours, poor working conditions, and the exploitation of workers, particularly in factories. His observations laid the groundwork for the development of socialist thought and were instrumental in raising awareness about workers' rights and social justice in the industrial age.