Hessen Hessen is situated in western-central Germany and is one of Germany's sixteen federal states. The capital was Kassel until 1945. After World War II the capital city was changed to Wiesbaden. Its economic center and largest city is nearby Frankfurt and the surrounding Rhine-Main Area. The area of Hesse was settled by the Chatti in the 1st century BC, and the name Hessen is a continuation of that tribal name. The main rivers in the northern part of Hesse are Fulda and Lahn. It is a hilly countryside, the main mountain chains being the Rhön, the Westerwald, the Taunus and the Spessart. Most inhabitants live in the southernmost part of Hesse between the rivers Main and Rhine. The latter borders Hesse on the southwest without running through the state. The mountain chain between the Main and the Rhine is called the Odenwald. In the early Middle Ages, Hesse was a part of Thuringia, but in the War of the Thuringian Succession, which lasted from 1247 to 1264, Hesse gained its independence and became a Landgraviate within the Holy Roman Empire. It shortly rose to primary importance under Landgrave Philip the Magnanimous, who was one of the leaders of German Protestantism. After Philip's death in 1567, the territory was divided up among his four sons from his first marriage into four lines Hesse-Kassel, Hesse-Darmstadt, Hesse-Rheinfels and Hesse-Marburg. As the latter two lines died out in 1583 and 1605, respectively, Hesse-Kassel and Hesse-Darmstadt became the two core states within the Hessian lands. Several collateral lines split off during the centuries, such as in 1622, when Hesse-Homburg split off from Hesse-Darmstadt. In the late 16th century, Kassel adopted Calvinism, while Darmstadt remained Lutheran and subsequently the two lines often found themselves on different sides of a conflict, most notably in the disputes over Hesse-Marburg and in the Thirty Years' War, when Darmstadt fought on the side of the Emperor, while Kassel sided with Sweden and France. Hesse-Kassel was elevated to the dignity of an Electorate in 1803, but this remained without effect as the Holy Roman Empire was disbanded in 1806. The territory was annexed by the Kingdom of Westphalia in 1806, but restored to the Elector in 1813. While other Electors had gained other titles, becoming either Kings or Grand-dukes, the Elector of Hesse-Kassel alone retained the anachronistic dignity. The name survived in the term Kurhessen, denoting the region around Kassel. In 1866 it was annexed by Prussia, together with the Free City of Frankfurt, Hesse-Homburg and the duchy of Nassau, which established the province of Hesse-Nassau. Hesse-Darmstadt was elevated to the dignity of a Grand Duchy in 1806. In the War of 1866, it fought on the side of Austria against Prussia, but retained its autonomy in defeat, because a greater part of the country was situated south of the Main river and Prussia did not dare to expand beyond the Main line as this might have provoked France. The parts of Hesse-Darmstadt north of the Main river, the region around the town of Gießen, commonly called Upper Hessen "Oberhessen", were incorporated in the North German Federation "Norddeutscher Bund", a tight federation of German states, established by Prussia in 1867. In 1871 the rest of the Grand Duchy joined the German Empire. The palace of Darmstadt is located in the city center. It was the residence of the counts of Hesse-Darmstadt, later as Grand Dukes of Hesse by the grace of Napoleon. The counts also owned a castle on the Langenberg above the city. This castle dates back to the 13th century, but it was acquired by the counts of Hessen-Darmstadt in 1662. The name of the castle is Frankenstein. Mary Shelley probably adopted the name for her novel Frankenstein in 1818. Before writing the story, she had travelled through the region and visited Eberstadt, today a borough of Darmstadt, so the castle could have given her the inspiration. The Landgraviate of Hesse-Darmstadt came into existence in 1568, as the portion of George, youngest of the four sons of Landgrave Philip I of Hesse. With the extinction of the Hesse-Marburg and Hesse-Rheinfels lines by 1604, Hesse-Darmstadt, along with Hesse-Kassel, became one of the two Hessian states. While Hesse-Kassel converted to Calvinism and became one of the most zealous exponents of the Protestant cause in the Thirty Years' War, Landgrave George II remained a strict Lutheran and maintained a close alliance with Saxony, which resulted in a pro-Habsburg policy after 1635. Hesse-Darmstadt gained a great deal of territory by the secularizations and mediatizations authorized by the Reichsdeputationshauptschluss of 1803. Most notable was the acquisition of the Duchy of Westphalia, formerly owned by the Archbishop of Cologne, as well as territories from the Archbishop of Mainz and the Bishop of Worms. In 1806, upon the dissolution of the Reich and the dispossession of his cousin, the Elector of Hesse-Kassel, the Landgrave took the title of Grand Duke of Hesse. At the Congress of Vienna, the Grand Duke was forced to cede Westphalia to Prussia, in exchange for which he received a piece of territory on the Left Bank of the Rhine, including the important federal fortress at Mainz. The Grand Duchy changed its name to the Grand Duchy of Hesse and by Rhine in 1816. In 1867, the northern half of the Grand Duchy (Upper Hesse) became a part of the North German Confederation, while the half of the Grand Duchy south of the Main (Starkenburg and Rhenish Hesse) remained outside. In 1871, it became a constituent state of the German Empire. The last Grand Duke, Ernst Ludwig (a grandson of Queen Victoria and brother to Empress Alexandra of Russia), was forced from his throne at the end of World War I, and the state was renamed the Volksstaat Hessen (People's State of Hesse). The majority of the state combined with Frankfurt am Main and the old Prussian province of Hesse-Nassau to form the new state of Hesse following the Second World War. The part of the state on the left bank of the Rhine (Rhenish Hesse) became part of the Rhineland-Palatinate state. With the revolution of 1918 Hesse-Darmstadt became a republic, calling itself officially the People's state Hesse "Volksstaat Hessen". The parts of Hesse-Darmstadt on the left bank of the Rhine were occupied by French troops until 1930 under the terms of the Versailles peace treaty that officially ended WWI in 1919. After World War II the Hessian territory left of the Rhine was again occupied by France, whereas the rest of the country was part of the US occupation zone. The French separated their part of Hesse from the rest of the country and incorporated it into the newly founded state of Rhineland-Palatinate, otherwise known as Rheinland-Pfalz. The US on the other side formed the state of Greater Hesse "Groß-Hessen" already in 1945, out of Hesse-Darmstadt and most of former Prussian province of Hesse-Nassau. On December 4, 1946 Groß-Hessen was officially renamed Hessen. Modern day Hessen borders on the German states of North Rhine-Westphalia, Lower Saxony, Thuringia, Bavaria, Baden-Württemberg and Rhineland-Palatinate. Its principal cities include Frankfurt am Main, Wiesbaden, Darmstadt,Offenbach, Gießen and Wetzlar in the greater Rhine Main Area, Fulda in the east, as well as Kassel and Marburg in the north.