Какая разница между inspite, despite, although?

In spite of + noun/-ing form - "несмотря на" (предлог), употребляется всегда с предлогом "of".
Despite + noun - тоже "несмотря на" (предлог), после него всегда употребляется существительное.
Although - "хотя", союз.

He has won the race in spite of the difficulties.
He has won the race despite the difficulties.
He has won the race although he had a lot of difficulties.