No specific PoD, but several major things are different:
The Reconquista fails. Castile, Aragon, and Leon remain separate. Al Andalus is reformed and reuinited by a powerful warlord and great tactician into a reconstituted Caliphate of Cordoba.
This results in a Basque wank, as the Basques revolt, establish their own state, and wage a successful war against Castile allied with Cordoba.
Meanwhile there is an England screw, as France and Scotland defeat it in war. The United Kingdom of Scotland and Wales is among the great powers of Europe. There has also been an Irish revolt, which has established a native Kingdom of Ireland.
The west slavs continue moving westwards, and the Sorbians establish a kingdom in eastern Germany. A group called the Bolobar migrate into what is now eastern Russia and establish a state there.
Finland unifies against Swedish attempts to conquer it and wipe out its culture. An army composed of several united tribes of Fins defeats a Swedish army and secures Finnish independence. Finland expands further at the expense of Sweden, annexing Sami areas and parts of Norway after the Great Finnish War. The Empire of Finland expands into Russia, and further inland Suomi is a trading lingua franca.
From the east a Turkish kingdom formed from ruins of the Seljuq Sultanate of Rum manages to expand and conquer a vast area extending from Mesopotamia to Egypt, the Georgia, to Mauritania, to Italy. Rome itself was conquered and made the capital by Imperator Sulimanus, who saw himself as an Islamic Constantine. The state is called the "Great and Universal Caliphate and Empire of the Romans". Royal Turkoman is the language of state and a lingua franca among the cultured elites and merchants.
The Helvetic romance language survives, and thrives during the Turkoman conquest of Italy. Italian refugees flooded Switzerland and adopted the language. A Kingdom of Helvetia is established soon after to unite the people against Turk conquest.
The Holy Roman Empire was broken up and destroyed by the western Slavs, who become great bastions of Catholicism in northern Europe.
The Frisian language survives and a Frisian kingdom expands and dominates northern Germany
Iceland has natives and its own language, it even developed a writing system.