2 Euros Constantin Carathéodory

Carathéodory was born in Berlin in 1873 and spent much of his career at German universities — Munich, Göttingen, Berlin — yet Greece claimed him for this commemorative on the 150th anniversary of his birth. The choice is defensible: he held a chair at the University of Athens and, following the catastrophic Greek defeat in the Greco-Turkish War, was tasked in 1920 with building the Ionian University of Smyrna from nothing, acquiring library collections and equipment across Europe before the city burned in 1922 and the project collapsed entirely.

His mathematical legacy rests primarily on his work in the calculus of variations and his axiomatic formulation of thermodynamics.