The official name reflects Hamburg 's history as a member of the medieval Hanseatic League and a free imperial city of the Holy Roman Empire . Before the 1871 Unification of Germany , it was a fully sovereign city state , and before 1919 formed a civic republic headed constitutionally by a class of hereditary grand burghers or . Beset by disasters such as the Great Fire of Hamburg , North Sea flood of 1962 and military conflicts including World War II bombing raids , the city has managed to recover and emerge wealthier after each catastrophe
North Sea flood of 1962
North Sea flood of 1962
Hamburg