See Robert Reich for the former U.S. Labor Secretary.

See Steve Reich for the composer.

See Wilhelm Reich for the psychologist.

Reich is the German word for "realm" or "empire", cognate with Scandinavian rike and Dutch rijk. It is the word traditionally used for sovereign entities, including Germany. For instance, any country with a King or Queen as head of state, such as Britain, is a Königreich (kingdom). It is still used as a suffix in certain country names, for instance Frankreich (France).

The term Reich was part of the official names of Germany over centuries. The German name for "Holy Roman Empire of the German Nation" (early 16th century – 1806) is Heiliges Römisches Reich Deutscher Nation. This was the First Reich. The Second Reich was the German empire under Chancellor Otto von Bismarck in the nineteenth century. Later, Deutsches Reich was the official name of Germany from 1871 to 1945, although its three very different political systems are commonly referred to as the German Empire (1871–1918), the Weimar Republic (1919–1933), and finally the Third Reich (Nazi Germany) (1933–1945).

The Nazis, eager to present their rule as a continuation of a Germanic past, used the term Das Dritte Reich ("The Third Reich"), counting the Holy Roman Empire as the first and the 1871 Empire as the second. They also used the political slogan "Ein Volk, ein Reich, ein Führer" ("One people, one country, one leader").

A number of words used by the Nazis which earlier were neutral have later taken on a negative connotation in German (e.g. Führer or Heil); the word "Reich" is usually not one of them, although in certain contexts it does carry a connotation of German imperialism and/or strong nationalism - mainstream modern Germans would not refer to their country as the Reich for that reason. The word is still used with the Reichstag building, which again, since 1999, houses the German federal parliament (today called Bundestag), and for the old Reichstag institution.

The German name of Austria is Österreich, or "Eastern Reich", and France is called Frankreich.

The German version of the Lord's Prayer uses the words Dein Reich komme for "thy kingdom come".

Cognates

• Swedish: Rike
• Old High German: richi
• Old English: rice
• Dutch: rijk
• English: rich (compare to commonwealth)
• Indo European: reg
• Latin: regalis, regere, rex
• Prussian: reiks
• Indian: Raj
• Old Norse: rike (as in Gårdarike).
• Lithuanian: reichas
• Polish: rzesza
• Czech: říše

The word reich (lower case) is also a German adjective and adverb for "rich" or "wealthy" / "richly", "wealthily".