Mark 5.1-10, Matthew 8.28-29, Luke 8.26-31.
Let’s begin with ancient northern Israel’s geography. First there’s Kinneret, the lake.

The Galilean sea.
On its northeast was the province of the Galilee, named for the word galýl/“circle,” referring to its circle of towns. Jesus lived there. On its west was the Dekápolis/“10 cities,” a region of Syrian Greek city-provinces created by the Romans after they conquered Syria in 65BC. Jesus visited this territory often, and it’s where today’s story takes place.
In Old Testament days the Dekápolis belonged to the Hebrews. Today part of it is called the Golan Heights. In Jesus’s day, even though it was full of Greek-speaking Syrians, it was still considered part of Israel, and still part of the territory Antipas Herod supervised. But it was full of gentile, Greek-enculturated pagans. They weren’t even Hebrew like the Palestinians are.
By Greek-enculturated I mean they lived like Greeks. Alexander of Macedon had pushed his own culture everywhere he went, and in fourth-century BC Syria it seriously took hold. Greek language, Greek dress, Greek food, Greek religion. The Syrians worshiped a mixture of Syrian, Canaanite, and Greek gods. I’ve been to their ruins; these people weren’t Jews by any stretch of the imagination. They were so Greek, whenever Jews thought of gentiles, they thought of these guys… and thought of Greeks.
The ruins include lots of monuments to Greek deities. The major deities were called theoí/“gods,” and the lesser deities were called daimónia/“demons.” Or as the KJV calls them, devils. To the Christian mind, all these deities are devils. 1Co 10.19-20 And they were everywhere. Anything and everything was dedicated to a god or demon. Every monument was set up to honor something or someone. If a noble human, there was a caveat that the monument also honored whatever guardian demon protected that person, so when you remembered the person, you were meant to also worship their demon. The hillside was full of these monuments. You could see them from the beach.
And that’s where our story begins: Jesus and his students, after crossing the lake, landed on the beach, in full view of a cluster of monuments. And in full view of some wild man who was living among the monuments, who eagerly—and in utter terror—rushed down to meet him.
Was he of two minds about meeting Jesus? More like of 2,001 minds. Dude was full of devils.