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 west of Kaiserslautern. The recovered relics are now in the Museum for Palatinate History at
Speyer.
Medieval period Kaiserslautern received its name from the favourite 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 Local legends claim in 1497, a nearly 6 m long pike was caught in a lake, the Kaiserwoog, with a ring saying it was placed by
Emperor Frederick II, personally in 1230, later finding its way onto the city's coat of arms. The
Stiftkirche, Kaiserslautern's oldest church, was constructed between 1250 and 1350. As the population of Kaiserslautern grew, King
Rudolf von Habsburg chartered the town as an imperial city in 1276.
St. Martin's Church was built in the 14th century, originally as a
Franciscan monastery church. Today a section of the original city wall still stands in the courtyard of the church. By 1375, the city of Kaiserslautern was pledged to
Electoral Palatinate Conflict did not end with the
Peace of Westphalia in 1648. The
Elector of the Pfalz had difficulty with many of his subjects and ordered all castles, including Nanstein, destroyed. The French repeatedly invaded and occupied the area, residing in Kaiserslautern from 1686 to 1697. Nevertheless, after the Treaty of Utrecht, it was restored to be part of the Palatinate. During the unquiet episodes in the 18th century, the Palatinate was the scene of fighting between French and German troops of different states. In 1713, the French destroyed Barbarossa's castle The railway and several main roads were primary targets, with the heaviest attacks occurring on 7 January, 11 August, and 28 September 1944. On 20 March 1945, as part of
Operation Undertone, as the last of the
1st Army crossed the
Rhine at
Remagen, the
U.S. 80th Division, 319th Infantry, part of the
3rd US Army, seized Kaiserslautern without resistance. American forces would occupy the city until July 1945, when it was transferred to their French counterparts. The city became part of the French occupation zone after the Second World War. The establishment of the state of Rhineland-Palatinate was ordered on 30 August 1946 as the last state in the western occupation zones by ordinance No. 57 of the French military government under General
Marie-Pierre Kœnig. Little reconstruction took place until the currency reform of 1948. The pace of the economy remained slow until 1952, when construction for newly established garrisons of American troops, in particular the nearby
Ramstein Air Base, brought economic growth to the area. Unexploded ordnance from WWII continues to be discovered in and around Kaiserslautern. In May 2012, an unexploded Allied bomb was found, buried deeply and reportedly covered by a water pipe, during a construction project in the downtown area of the city. On 5 September 2013, another WWII bomb was found during construction near the train station in Enkenbach-Alsenborn.
Cold War era In the late 1940s, the Kaiserslautern area became the largest U.S. garrison outside the United States (
Kaiserslautern Military Community). On 14 November 1956, a U.S. Air Force F-86 fighter jet crashed into the district office in the Burgstrasse / Maxstrasse area. In addition to the pilot, two civilians were killed, and numerous others were wounded. With the incorporation of the previously independent communities of Dansenberg, Erfenbach, Erlenbach, Hohenecken, Mölschbach, Morlautern and
Siegelbach on 7 June 1969, Kaiserslautern became a city. The University of Kaiserslautern was founded in 1970. Industry flourished around the time of the first oil crisis (1973). In the 1970s, many industrial companies went through a crisis. In 1981, the spinning mill went bankrupt;
Pfaff and
Opel fired employees. The downsizing of the American garrison and the withdrawal of the French garrison cost more jobs.
21st Century In 2002, renovations of the
Fritz-Walter-Stadion began, concluding in 2006 ahead of the
2006 FIFA World Cup. In 2015, a mall called "K-in-Lautern", opened. During the
COVID-19 pandemic, a joint German-US response to the crisis was carried out in the city. The city's economy recovered well after the pandemic, hosting its first local
Pride parade and
Oktoberfest in 2025. == Climate ==