In SOLDIERS OF REVOLUTION, historian Mark A. Lause analyzes changes in European warfare in the closing decades of the 19th century and the consequences for working-class movements. The Franco-Prussian War of 1870–71 introduced new military technologies, transformed the organization of armies, and upset the continental balance of power. The mass armies that became a new standard required mass mobilizations of working people, who exercised a new power through social democratic parties and insurgent movements.