| Karl Alexander | |
| Full Name: | German: Karl Alexander |
| Prince of Thurn and Taxis | |
| Reign: | 13 November 1805 – 15 July 1827 |
| Reign-Type: | Period |
| Predecessor: | Karl Anselm |
| Successor: | Maximilian Karl |
| Succession: | Head of the House of Thurn and Taxis |
| Spouse: | Duchess Therese of Mecklenburg-Strelitz |
| Issue: | Princess Charlotte Luise Prince Georg Karl Maria Theresia, Princess Esterházy of Galántha Princess Luise Friederike Maria Sophia, Duchess Paul Wilhelm of Württemberg Maximilian Karl, 6th Prince of Thurn and Taxis Prince Friedrich Wilhelm |
| House: | Thurn and Taxis |
| Father: | Karl Anselm, 4th Prince of Thurn and Taxis |
| Mother: | Duchess Auguste of Württemberg |
| Birth Date: | 22 February 1770 |
| Birth Place: | Imperial City of Regensburg, Kingdom of Germany, Holy Roman Empire |
| Death Place: | Schloss Taxis, Dischingen, Kingdom of Württemberg |
| Burial Place: | St. Emmeram's Abbey |
Karl Alexander, 5th Prince of Thurn and Taxis, full German name: Karl Alexander Fürst von Thurn und Taxis (22 February 1770 – 15 July 1827) was the fifth Prince of Thurn and Taxis, head of the Thurn-und-Taxis Post, and Head of the Princely House of Thurn and Taxis from 13 November 1805 until his death on 15 July 1827. With the death of his father on 13 November 1805, he became nominal Generalpostmeister of the Imperial Reichspost until the resignation of Francis II, Holy Roman Emperor.
Karl Alexander was born as the son of Karl Anselm, 4th Prince of Thurn and Taxis and his first wife, Duchess Auguste of Württemberg.[1] He studied at the Universities of Strasbourg, Würzburg, and Mainz and then subsequently went on a European tour. In 1797, he was appointed successor to his ailing father's position as Prinzipalkommissar at the Perpetual Imperial Diet in Regensburg. Karl Alexander also worked for the Thurn and Taxis postal empire, operating during a decline due to the gradual loss of territory as a result of the Napoleonic Wars.
Karl Alexander married Duchess Therese of Mecklenburg-Strelitz, fourth eldest child and third eldest daughter of Charles II, Grand Duke of Mecklenburg and his wife Princess Friederike of Hesse-Darmstadt, on 25 May 1789 in Neustrelitz, Mecklenburg-Strelitz. Karl Alexander and Therese had seven children:
After the end of the Holy Roman Empire, the Thurn and Taxis postal system continued to survive as a private company. Since 1806, Karl Alexander headed a private postal company, the Thurn-und-Taxis Post. It existed first as a feud of some of the Confederation of the Rhine members, such as Baden, Bavaria, and Württemberg. Bavaria nationalised the postal system two years later. After the Congress of Vienna, Karl Alexander took over the Hessian and Thuringian postal services, as well as those in the Hanseatic League cities of Bremen, Hamburg, and Lübeck, and Schaffhausen. From 1820, the company began to prosper again, so Karl Alexander began to acquire large amounts of land holdings.
According to the Confederation of the Rhine Act, agreed upon between Napoleon I of France and the Confederation of the Rhine princes, the Principality of Thurn and Taxis lost its independence and was mediatised in 1806. Since then, the Princes of Thurn and Taxis and hence Karl Alexander, depending on the territory, were subjects of either the King of Württemberg, or the Princes of Hohenzollern-Sigmaringen. In return, the House of Thurn and Taxis received the Imperial Abbey of St. Emmeram and associated territories in Regensburg. Karl Alexander also received as the family head of the House of Thurn and Taxis, Prussian possessions in the Grand Duchy of Poland. In 1822/23, he bought from the Count Kinsky and others the Burg Reichenburg in Liberec Bohemia.
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