The modern national state of Germany is, as an international subject and as a legal entity, identical to the North German Confederation. Law and international treaties of the era 1867-1870 are in principle still valid. In a conservative-liberal cooperation lasting from 1867 to 1878, Germany saw a remarkable modernisation and unification. The North German Confederation introduced the metric system, a modern penal code (Strafgesetzbuch), same rights for all denominations, a postal union etc.