The colours of the Realm are black-red-gold. The commercial flag is black-white-red with the national colours in the inner upper corner.[4]
The generally recognised rules of international law are held to be integral and obligatory parts of the Law of the German Realm.[5]
Article 5.
Constitutional power shall be exercised, in matters pertaining to the Realm, by the Constitutional Bodies of the Realm on the basis of the constitution of the Realm, in matters pertaining to the Lands, by the constitutional bodies of the Lands on the basis of the constitutions of the Lands.
Article 6.
The Realm has exclusive legislative authority in:—
(1) Foreign relations.[6]
(2) Colonial affairs.[7]
(3) Nationality, freedom of domicile, immigration and emigration, extradition.