Colonel (Oberst) Ernst Heidrich was a serving officer in the KuK (Imperial and Royal) army when he wrote his exceptionally detailed monograph ‘Der Kampf Um Den Svibwald Am 3. Juli 1866’ (The battle for the Swiepwald 3rd July 1866, Sadowa Press 1902). Particulars of the Colonel’s early life are sparse, but we know he was born in Horschitz (Horice) and attended the high school in Hradec Kralove (Königgrätz), before being commissioned into the KuK Army. He seems to have served principally as an administrative officer, first as pharmacy superintendent in the fortress hospital at Josefov between 1880 – 1900, and later in the same capacity at Sarajevo (Bosnia). In the decennial Imperial census of 1900, Heidrich recorded his nationality as Czech not German (possibly to the detriment of his military career). He was living in Prague in 1918 when the empire finally collapsed and died there in 1922.