When reading about the history of the many German kingdoms, grand duchies, duchies, and principalities, a few terms will probably be noticed.
Holy Roman Empire
The Holy RomanEmpire on the eve of the French Revolution, 1789; Credit – By Robert Alfers, kgberger – Source of Information: Putzger – Historischer Weltatlas, 89. Auflage, 1965; Westermanns Großer Atlas zur Weltgeschichte, 1969; Haacks geographischer Atlas. VEB Hermann Haack Geographisch-Kartographische Anstalt, Gotha/Leipzig, 1. Auflage, 1979; dtv-Atlas zur Weltgeschichte Band 1: Von den Anfängen bis zur Französischen Revolution; 23. Aufl. 1989, ISBN 3-423-03002-X, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=4179496
The Holy Roman Empire was also known as the Holy Roman Empire of the German Nation, which is a better description because the Holy Roman Empire was neither Holy, Roman nor an Empire. It was a decentralized, limited elective monarchy composed of hundreds of predominantly German kingdoms, principalities, duchies, counties, prince-bishoprics, and Free Imperial Cities. The Holy Roman Emperor was traditionally elected although it was frequently controlled by dynasties. The power of the Holy Roman Emperor was limited. The rulers of the hundreds of kingdoms, principalities, duchies, counties, prince-bishoprics, and Free Imperial Cities owed their allegiance to the Holy Roman Emperor but they had independence within their territories. The Holy Roman Empire developed during the Early Middle Ages and continued until its dissolution in 1806 during the Napoleonic Wars.
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The German Confederation
Map of the German Confederation; Credit – By ziegelbrenner, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=3414903
The German Confederation was an association of 39 German-speaking countries in Central Europe, along with the Kingdom of Bohemia and Duchy of Carniola, created by the Congress of Vienna in 1815 to coordinate the economies of the German-speaking countries and to replace the former Holy Roman Empire, which had been dissolved in 1806. The German Confederation was dissolved after the victory of the Kingdom of Prussia over the Austrian Empire in the Seven Weeks’ War in 1866.
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The North German Confederation
Map of the North German Confederation (Prussia with its provinces are shown in blue); Credit – By Ziegelbrenner – own drawing/Source of Information: Putzger – Historischer Weltatlas, 89. Auflage, 1965; Westermanns Großer Atlas zur Weltgeschichte, 1969; Haacks geographischer Atlas. VEB Hermann Haack Geographisch-Kartographische Anstalt, Gotha/Leipzig, 1. Auflage, 1979; dtv-Atlas zur Weltgeschichte Band 1: Von den Anfängen bis zur Französischen Revolution; 23. Aufl. 1989, ISBN 3-423-03002-X, CC BY 2.5, https://commons.wikimedia.org/w/index.php?curid=33150558
The North German Confederation existed from July 1867 to December 1870. It was a confederacy of equal states but it was controlled and led by the largest and most powerful member, the Kingdom of Prussia, which exercised its influence to bring about the formation of the German Empire.
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The German Empire
The constituent states of the German Empire; Credit – Wikipedia
The German Empire existed from the unification of Germany in 1871 until the abdication of Emperor Wilhelm II in 1918 after World War I when all the constituent monarchies in the German Empire were abolished. The German Empire consisted of 26 states, most of them ruled by royal families. They included four kingdoms, six grand duchies, five duchies, seven principalities, three free Hanseatic cities, and one imperial territory. The King of Prussia was also the German Emperor (Kaiser) and the capital of the German Empire was Berlin. The member states retained their own governments but lost some aspects of sovereignty. For example, both postage stamps and currency were issued for the empire as a whole.