Today and ever since human beings interacted, addressing each other constituted a vital part of communication. Over time most languages of Indo-European origin developed distinctive forms of address, mostly by means of binary systems comprising a polite and an informal form. The English system of address pronouns, on the other hand, is characterised by the unique development of the plural pronoun ''you'' virtually ousting its singular counterpart ''thou''. This work looks into this development with regard to linguistic, social, historical, and literary aspects. The main part of the work thus focuses on the history of English address pronouns from Old English to the present day. A diachronic description of the High German address pronoun system, distinguishing itself by going through an extreme variety of forms from its origins up to its modern standard usage, shall serve as a basis for a comparative analysis of the two systems and shed light on the immense influence social and historical factors have on language. ''You and Thou'' addresses students of diachronic linguistics as well as anybody interested in the history of English and German, and particularly their address term systems.