Wanyama says Tottenham's supporters helped convince him to join.
The midfielder had just one year left on his deal at the Saints, and is relishing the opportunity to play Champions League football, after Spurs finished inside the top four.
Southampton's Victor Wanyama shoots at goal
In addition to the chance to play against Europe's best, Wanyama has also described Tottenham Hotspur's supporters as being a factor in his decision to join the club, commenting that he was impressed with them whenever he faced the North London side with Southampton.
Wanyama told Tottenham's official club website: "I’ve played at the Lane a few times and it’s a tough place to come from the opposition side.
"Now being a Spurs player, it’s going to be great walking out of the tunnel and seeing the home fans cheering on the team so I’m looking forward to it.
"From outside you can see that the club has a great fan base and that’s one of the things that attracted me here."
Manchester City's Samir Nasri in action with Southampton's Victor Wanyama
Wanyama's combative style puts him in with a chance of becoming a real fan favourite at Tottenham, coupled with his sometimes off-beat comments on social media.
He is likely to have a prominent role in pre-season and early on in the campaign with Tottenham's Euro 2016 stars due a lengthier rest, while Mousa Dembele is also suspended for the first three matches of the Premier League season.
Right now he is saying all the right things, and it's only a matter of time before supporters get to cheer him on in action.