Breaking new ground in the intellectual history of economic and social human rights, Christian Olaf Christiansen traces their justification from the outset of World War II until the present day. Featuring a series of fascinating thinkers, from political scientists to Popes, this is the first book to comprehensively map the key arguments made in defense of human rights and how they connect to ideas of social and redistributive justice. Christiansen traces this intellectual history from a first phase devoted to internationalizing these rights, a second phase of their unprecedented legitimacy deployed to criticize global inequality, to a third phase of a continued quest to secure their legitimacy once and for all. Engaging with the newest scholarship and building a bridge to political philosophy as well as global inequality studies, it facilitates a much-needed novel and nuanced history of rights-rights we should still consider defending today.