Prehistoric settlement in the area of what is now Kaiserslautern has been traced to at least 800 BC. Some 2,500-year-old Celtic tombs were uncovered at Miesau, a town about 29 kilometres west of Kaiserslautern. The recovered relics are now in the Museum for Palatinate History at Speyer.
Kaiserslautern received its name from the favorite hunting retreat of Holy Roman Emperor Frederick Barbarossa who ruled the Holy Roman Empire from 1155 until 1190. The small river Lauter made the old section of Kaiserslautern an island in medieval times. Ruins of Frederick's original castle, built 1152�1160, can still be seen in front of the Rathaus (city hall). A second castle, Nanstein Castle, was built at Landstuhl to guard the western approach to the city. Because of the influence Frederick Barbarossa had on the town, it is nicknamed a "Barbarossa town".
The Stiftkirche, Kaiserslautern's oldest church, was constructed in 1250�1350. As the population of Kaiserslautern grew, King Rudolf von Habsburg chartered the town in 1276. St. Martin's Kirche (church) was built from 1300�1350 for an order of monks. Today a section of the original city wall still stands in the courtyard of the church.
In 1375, the city of Kaiserslautern was put into pawn to the Kurpfalz and therefore became subsequently part of the Wittelsbach heirloom. In 1519, Franz von Sickingen became the owner of Nanstein Castle. He became a Protestant, and in 1522 Nanstein was a stronghold for local nobles favouring the Reformation. Sickingen and the local nobles began their battle against the Archbishop of Trier; but the attack was unsuccessful, and they retreated to Nanstein. Nanstein was then besieged by cannon-armed German Catholic princes. Sickingen died after the castle surrendered, and the Protestant nobility of the Electorate of the Palatinate were subdued by the Catholic princes.
Count of the Electorate of the Palatinate Johann Casimir, came to Kaiserslautern during the Thirty Years'
