On social media, Ramsey first thanked his former side OGC Nice, before going on to share his excitement at his return to Cardiff.
“Before I start my new chapter I have to say a huge thank you to OGC Nice football club and all of the brilliant people I have had the pleasure of getting to know,” Ramsey wrote.
“There is so much potential in the club and I hope it goes from strength to strength.
“It’s an unbelievable feeling to be back at home- although I feel as if I never really left.
“Wherever I went it was always a part of me and now I can’t wait to go out there in the blue shirt again.
“What makes it even better was my boy (Sonny Ramsey, Aaron’s oldest son) also signed for Cardiff Academy the same day which was a special moment for us both.”
Cardiff are under a transfer embargo after defaulting on the initial payment of Emiliano Sala’s £15m transfer fee, so they’re only allowed to sign players on free transfers.
Ramsey reportedly drew interest from other clubs, but he was always eager to move back to Wales with his family.
Speaking to the BBC in June, the midfielder said: “For sure one day I would love to go back there [Cardiff City].
“It’s where I grew up and them giving me that opportunity and platform to go on to what I have achieved so far in my career, I will forever be grateful.
“The most important thing for me is to enjoy my time off now with my family and to make the right decision going forward for us.”
This will be Ramsey’s third stint with Cardiff, the club from which Arsenal signed him in the first place.
After completing that permanent transfer in 2008, Ramsey later went back to Wales on loan in 2011 to build his match fitness.
The 32-year-old has since played for Juventus, Rangers, and most recently Nice, but it looks like he’s finally set to make a more permanent return to his home country.
Ramsey made 34 appearances for Nice last season, scoring once and assisting three times.