What happened in 1259? — events across the world

West Asia

Launch of the First Crusade
1095–1291Jerusalem
In November 1095, Pope Urban II officially called for Christians to take up arms and reconquer Jerusalem at the Council of Clermont, launching the First Crusade and inaugurating a series of crusades that continued until 1291. The call promised spiritual rewards, and the success led to the establishment of four Crusader states in the Levant.
SourcesWikipedia ↗
Founding of Maragheh Observatory
1259
In 1259, under the patronage of Ilkhanid Hulagu and the directorship of Persian scholar al-Tusi, the Maragheh observatory was established in Iran, becoming one of the most advanced scientific institutions in Eurasia.
SourcesWikipedia ↗
Mongol invasions of Anatolia
1241–1335
The Mongol invasions of Anatolia began in 1241 with attacks on the city of Kâlin, culminating in the Battle of Köse Dağ in 1243. After the Seljuk defeat, the Sultanate of Rum submitted, and the Mongols assumed control over Anatolia. In 1255, following repeated Seljuk rebellions, Mongol forces swept through central and eastern Anatolia and stationed a garrison near Ankara. Their effective rule lasted until the collapse of the Ilkhanate in 1335.
SourcesWikipedia ↗

Signing of the Treaty of Paris (1259)
1259Paris
On December 4, 1259, King Henry III of England and King Louis IX of France signed the Treaty of Paris, ending over a century of Capetian–Plantagenet conflict. Henry III renounced Normandy (except the Channel Islands), Maine, Anjou, and Poitou, but was allowed to hold Gascony and part of Aquitaine as a vassal of Louis IX, who in turn ceased supporting rebellions against England.
SourcesWikipedia ↗
Founding of Sopoćani Monastery
1259World Heritage
In the late 13th century, King Stefan Uroš I of Serbia commissioned the Sopoćani Monastery near the source of the Raška River, with construction lasting from about 1259 to 1270. Located in the region of Ras, the medieval Serbian heartland, the monastery's church became a notable example of religious art upon completion.
SourcesWikipedia ↗
Rebuilding of Stolzenfels Castle
1259World Heritage
A medieval castle was built near Koblenz on the left bank of the Rhine around the 13th century and later fell into ruin. In the 1820s, the Prussian crown prince acquired the ruin, and some years later had it rebuilt as a Gothic Revival palace. Today, it is part of the UNESCO World Heritage Site Upper Middle Rhine Valley.
SourcesWikipedia ↗

Mongol invasions and conquests
1206–1337Karakorum, Mongol Empire capital
After the founding of the Mongol Empire in the early 13th century, Genghis Khan and his descendants launched a series of expansion wars across Eurasia, creating the largest contiguous land empire in history within a century and profoundly reshaping the political landscape of Eurasia.
SourcesWikipedia ↗

Mongol conquest of China begins
1205–1279Western Xia
In the early 13th century, the Mongol Empire under Genghis Khan initiated small-scale raids into Western Xia in 1205 and 1207, marking the beginning of a decades-long conquest of China. The conflict later escalated into full-scale campaigns against various Chinese dynasties.
SourcesWikipedia ↗

These are known only to the century, not to the year. They are listed separately so a rough date is never mistaken for an exact one.