Order of the Iron Crown (Austria)
The Holy Roman Empire, ruled by the Habsburg dynasty, gave way to the Empire of Austria between 1804 and 1806. The last Holy Roman Emperor, Franz II, was proclaimed Emperor Franz I of Austria. His daughter, the Archduchess Maria Louise, was Napoleon’s second wife and Empress Consort, and the mother of Napoleon’s only legitimate son and heir, Napoleon, Duke of Reichstadt. With the collapse of Napoleon’s empire, Imperial Austria regained its traditional control of Lombardy as the Kingdom of Lombardy–Venetia.
East Roman army
In 395, the death of the last sole Roman emperor, Theodosius I (r. 379-95), led to the final split of the empire into two political entities, the West ("Occidentale") and the East ("Orientale"). The system of dual emperors (called "Augusti" after the founder of the empire, Augustus) had been instituted a century earlier by the great reforming emperor Diocletian (r.284-305). But it had never been envisaged as a political separation, purely as an administrative and military convenience. Decrees issued by either emperor were valid in both halves and the successor of each "Augustus" required the recognition of the other. The empire was reunited under one emperor under Constantine I, after 324, under Constantius II, after 353, under Julian, after 361, and Theodosius himself, after 394.