Pfeffingen Castle is one of the largest castle ruins in the canton Basel-Land. In the area around Aesch and Pfeffingen existed originally a Franconian royal court. However, no remains have preserved from this time. In 1135 Notker von Pfeffingen was mentioned for the first time, which was probably related to Count von Saugers.
At the end of the 12th century, the Pfeffingen castle fell to the Count of Thierstein. In 1212 a family of Schaffner von Pfeffingen, who lived in the castle, was mentioned for the first time. In the mid-13th century the castle was comprehensively rebuilt. At this time, the curtain wall and the large residential tower were built. In 1335, the Bishop of Basel besieged the castle without success.
The great earthquake of Basel damaged Pfeffingen castle in 1356. When the Counts of Thierstein-Pfeffingen tried to expand their rule, it led into conflict with the city of Basel, whereupon Basel army successfully besieged the castle in 1376 and burned it down. The castle was restored after it.
In the 15th century Pfeffingen was conquered several times in wars between Austrian Habsburgs and Swiss armies (during the Old Zürich War). The castle, heavily damaged by the numerous wars, could not be maintained. In 1571, a new residential building was built as a replacement for the old residential tower, and a tower-defended gate and a bridge were built in the eastern part of the complex.
In the Thirty Years' War in 1637 the castle was occupied by Swedish troops under Bernhard of Saxe-Weimar and only eleven years later left in very poor condition to the bishop. Around 1750 the castle was finally abandoned by the Blarer family of Wartensee, who moved to the Aesch castle. Afterwards, a hermit lived temporarily in the castle. In 1761, the castle was auctioned on demolition and then fell rapidly.
After preparatory work in 2011 and 2012, construction work began in May 2013, overseen by ZPF Ingenieure. As the lime mortar that is used here can only be worked with when there is no frost, i.e. in the warmer half of the year, the work will take around six years. As the largest and most seriously damaged part of the ruins, the residential tower is to be reconstructed first. Here, there is a particular focus on sealing the coping and structurally securing unstable sections. The goal of the work is to repair the existing damage and to preserve the historical structure.
From its origin as a small stronghold built by the ancient Illyrian tribe Dalmatae, becoming a royal castle that was the seat of many Croatian kings, to its final development as a large fortress during the Ottoman wars in Europe, Klis Fortress has guarded the frontier, being lost and re-conquered several times. Due to its location on a pass that separates the mountains Mosor and Kozjak, the fortress served as a major source of defense in Dalmatia, especially against the Ottoman advance, and has been a key crossroad between the Mediterranean belt and the Balkan rear.
Since Duke Mislav of the Duchy of Croatia made Klis Fortress the seat of his throne in the middle of the 9th century, the fortress served as the seat of many Croatia"s rulers. The reign of his successor, Duke Trpimir I, the founder of the Croatian royal House of Trpimirović, is significant for spreading Christianity in the Duchy of Croatia. He largely expanded the Klis Fortress, and in Rižinice, in the valley under the fortress, he built a church and the first Benedictine monastery in Croatia. During the reign of the first Croatian king, Tomislav, Klis and Biograd na Moru were his chief residences.
In March 1242 at Klis Fortress, Tatars who were a constituent segment of the Mongol army under the leadership of Kadan suffered a major defeat while in pursuit of the Hungarian army led by King Béla IV. After their defeat by Croatian forces, the Mongols retreated, and Béla IV rewarded many Croatian towns and nobles with 'substantial riches'. During the Late Middle Ages, the fortress was governed by Croatian nobility, amongst whom Paul I Šubić of Bribir was the most significant. During his reign, the House of Šubić controlled most of modern-day Croatia and Bosnia. Excluding the brief possession by the forces of Bosnian King, Tvrtko I, the fortress remained in Hungaro-Croatian hands for the next several hundred years, until the 16th century.
Klis Fortress is probably best known for its defense against the Ottoman invasion of Europe in the early 16th century. Croatian captain Petar Kružić led the defense of the fortress against a Turkish invasion and siege that lasted for more than two and a half decades. During this defense, as Kružić and his soldiers fought without allies against the Turks, the military faction of Uskoks was formed, which later became famous as an elite Croatian militant sect. Ultimately, the defenders were defeated and the fortress was occupied by the Ottomans in 1537. After more than a century under Ottoman rule, in 1669, Klis Fortress was besieged and seized by the Republic of Venice, thus moving the border between Christian and Muslim Europe further east and helping to contribute to the decline of the Ottoman Empire. The Venetians restored and enlarged the fortress, but it was taken by the Austrians after Napoleon extinguished the republic itself in 1797. Today, Klis Fortress contains a museum where visitors to this historic military structure can see an array of arms, armor, and traditional uniforms.