Abstract The present paper is concerned with overt marking of definiteness, and to a lesser extent indefiniteness, in Germanic and Balto-Slavic from a historical perspective, concentrating on the main functional or formation types as well as general aspects of the historical development of (in)definiteness marking in the Germanic, Baltic and Slavic languages. By way of conclusion, I offer some tentative areal perspectives concerning definiteness marking in Germanic and Balto-Slavic.