Born in Carúpano, Venezuela, in 1867 and raised in Trinidad, Hahn was educated at Queen's Royal College before continuing his studies in Hamburg and at Berlin's Polytechnic School of Engineering. He returned as chief draughtsman of the Public Works Department, the post from which he designed Trinidad's two most conspicuous early-twentieth-century public buildings. The Water Riots of March 1903 gutted the old Red House; Hahn rebuilt it in dressed stone, adding the central cupola and Wedgwood-blue gesso ceiling that give the reopened Parliament of 1907 its silhouette. In between, on 11 November 1902, he laid the foundation stone of his own old school, Queen's Royal College, in a German Renaissance vocabulary of twin towers rather than the Red House's Beaux-Arts idiom. No death date for Hahn has been established in the sources consulted.
