Bale left Spurs in 2013 for the Bernabeu though struggled in recent times at the La Liga giants, frozen out by Zinedine Zidane.
But he is now back in the Premier League returning to Tottenham on an initial loan deal.
"It's nice to be back. It's such a special club to me," Bale said in an interview posted on the club's Twitter.
"It's where I made my name and what an amazing club, amazing fans.
"It's just incredible to be back and hopefully now I can get some match fitness and get under way and really help the team, and hopefully win trophies."
"I always thought when I did leave that one day I would love to come back. The opportunity now has arisen and I feel like it's a good fit.
"I feel like it's a good time for me. I'm hungry, I'm motivated, I want to do well for the team and I can't wait to get started."
Bale’s seven years at Real Madrid saw him win four Champions League titles, including playing starring roles in two of the finals.
He also won La Liga twice, though made just 16 appearances during last season’s success, with two goals.
Bale had spent six campaigns with Tottenham before heading to the Spanish capital, being named PFA Players' Player of the Year in both 2011 and 2013.
He will now work under Jose Mourinho with Tottenham being a very different side to the one he left seven years ago.
Bale is not expected to make his return bow until October as he looks to get up to speed with Tottenham.
Spurs will look to bounce back from an opening weekend Premier League defeat to Everton as they face Southampton on Sunday.