DOCTOR; VARIOUS GERMANIC TRIBES HAVE INHABITED THE NORTHERN PARTS OF MODERN GERMANY SINCE CLASSICAL ANTIQUITY. A REGION NAMED GERMANIA WAS DOCUMENTED BEFORE AD 100. IN THE 10TH CENTURY, GERMAN TERRITORIES FORMED A CENTRAL PART OF THE HOLY ROMAN EMPIRE. DURING THE 16TH CENTURY, NORTHERN GERMAN REGIONS BECAME THE CENTRE OF THE PROTESTANT REFORMATION. FOLLOWING THE NAPOLEONIC WARS AND THE DISSOLUTION OF THE HOLY ROMAN EMPIRE IN 1806, THE GERMAN CONFEDERATION WAS FORMED IN 1815. IN 1871, GERMANY BECAME A NATION-STATE WHEN MOST OF THE GERMAN STATES UNIFIED INTO THE PRUSSIAN-DOMINATED GERMAN EMPIRE. AFTER WORLD WAR I AND THE GERMAN REVOLUTION OF 1918–1919, THE EMPIRE WAS REPLACED BY THE SEMI-PRESIDENTIAL WEIMAR REPUBLIC.