We assist clients who wish to find whether they hold German citizenship. Such research requires providing often a detailed family background, sometimes going back years.
The following briefly summarizes a few historic facts of German citizenship that are preceding the current law of Citizenship in Germany. German citizenship can be obtained by birth according to § 4 Staatsangehörigkeitsgesetz (“StAG” German Citizenship Law). Under that provision, if one parent was a German citizen at the time of your birth, you may have derived German citizenship.
German citizenship law is based upon "Jus Sanguinis" (meaning “principle of descent”). That means - in general - that German citizenship is obtained by having a German father or (since 1974) a German mother at the time of birth. This concept is different from the U.S. system of obtaining citizenship by birth on U.S. territory.
Already prior to 1871, a type of citizenship law existed under the "Norddeutscher Bund" (Northgerman Alliance) known as "Gesetz über die Erwerbung und Verlust der Bundes-.und Staatsangehörigkeit" (Law concerning obtaining and loss of Federal and State Citizenship") of June 23, 1870. The Northgerman Alliance was a loose alliance of various states located north of the rivers Rhine and Main.
This citizenship law referred first to being a citizen of the member state and in second step considered them citizen of the Northgerman Alliance (The “Bund”). According to §§ 13 and 21 of said law the German citizenship was lost, if - the Northgerman - resides abroad for 10 years. The 10 year residence abroad requirement was shortened to 5 years if the [German] also naturalized in another country. However, according to § 21 of this law, the 10/5 years can be interrupted by filing into the "Matrikel" (Register) at the German Consulate abroad. Also, the 10 year deadline started to run upon the date of departure or – in case the citizen held a ‘travel paper’ (Reisepapier) or a certificate of residence (Heimatschein) – the expiration date of such paper. The latter did not apply if one applied for citizenship of another country.
With the formation of the Bismarckreich on 1.1.1871 and various other laws between the member states, the citizenship law above became binding for all member states, including the states located in the South of Germany. The words "North German" and "Bund" (Federal Government) were changed to "German" and "Reichsangehörigkeit" (referring to the German Empire). Still, it was based upon the presumption that all member states have their own citizen and that being a citizen of a member then has the indirect result of being a citizen of the German Empire "Deutsches Reich". This legal concept was known as "Vermittlungsprinzip", referring to becoming an (indirect) citizen of the German Empire by being a (direct) citizen of a member state. As such the member state served as a type of agency (“Vermittler”).
Over 40 years later, the RuStAG of 1913 (Reichs.-und Staatsangehörigkeitsgesetz of July 22, 1913 the German Citizenship Law of 1913) became the law. Of course, it underwent various changes and major reforms until now. The text of the current Citizenship law is available in English here.
In addition to that the German Constitution (German Grundgesetz) defines in Article 116 “German and Restoration of German Citizenship here.