In Germany at the close of the eighteenth century, Johann Gottfried Herder offered an important alternative to the philosophy of his teacher, Immanuel Kant. He held radical views on language, world history, the equality of all peoples, the role of climate in human life, and other topics that remain important to this day. He explored how these ideas might lead to radical intellectual practices and politics, providing an alternative to Eurocentric and racist ways of thinking. Writing in the wake of the French Revolution, Herder attempted to develop a political philosophy that would do justice to all humanity. His Letters for the Advancement of Humanity provides his mature statement on this project, available to English readers now for the first time in its entirety. An introduction situates the work within Herder's thought, and comprehensive notes provide access to its wider context.