Wodan and the Scandinavian Warlords

The dominant role of Wodan as the “Allfather” in Old Norse literature is a well-known fact or perhaps even common knowledge. Nevertheless, Heathenism has constantly been changing in symbiosis with its culture and society over the centuries, and so has the concept of Wodan. The question is: how did he become the alfǫðr Óðinn of the late Viking Age and which position did he have in the preceding eras?