The department is named after its two main rivers, the Ille and the Vilaine, whose confluence is in Rennes, the capital of the department and of the region.
Zaradi vse večjih zavezniških zračnih uspehov so septembra 1944 ponovno poklicali v bojno službo; postal je poveljnik enote, poimenovane po njem - Kommando Nowotny, ki je bila opremljena z reaktivnimi lovci Messerschmitt Me 262.