So far, what has had the biggest influence on the route Odysseus takes home?

Soon after leaving Troy on his way home Odysseus has a keep running in with the Cyclops Polyphemus - who needs to eat the greater part of Odysseus' group.

Odysseus isn't cheerful about this, he plays a trap on Polyphemus which winds up with Polyphemus visually impaired and Odysseus getting away with the greater part of his group uneaten.

The inconvenience is: Polyphemus is the child of Poseidon, and Poseidon is the divine force of the sea.