This volume serves as the comprehensive index and final reference tool for the monumental collection of correspondence written by the Renaissance humanist Desiderius Erasmus. The work provides the necessary scholarly apparatus to navigate the preceding eleven volumes, offering researchers and historians a systematic way to locate specific individuals, theological debates, and historical events mentioned throughout Erasmus's extensive epistolary output. By organizing these primary sources, the volume facilitates a deeper understanding of the intellectual network that defined European humanism.

Experts consider this index an indispensable tool for scholars working with the primary source material of the Northern Renaissance. Readers frequently note the high level of academic rigor and the meticulous organization required to synthesize such a vast body of historical correspondence.