"To get the opportunity to live in the UK, to play for such a powerhouse club that I believe is on the rise is something I'm looking forward to and hopefully I can add value to the team."
Warrington Wolves CEO Karl Fitzpatrick said the signing was a "historical moment" for the club.
"This signing is a gift to every one of our fantastic members and partners who are currently experiencing difficult times," Fitzpatrick said.
"We wanted to give everyone something to look forward to and to say thank you for their extraordinary loyalty. With this in mind we were extra motivated to get this deal completed.
"Greg is considered to be one of the greatest Rugby League players of the modern era. To see him pull on the primrose and blue will be a historical moment in Warrington Wolves and Super League's timeline."
Head Coach Steve Price believed Inglis would have a "positive impact" on the Warrington Wolves, who are yet to win a Super League title despite reaching the final on four occasions.
"Greg is a world-class athlete and has received the highest honours within our game," Price said.
"Having had 12 months out of the sport he has had time to refresh both mentally and physically, and he is focused on having a positive influence on Warrington Wolves.
"I'm looking forward to working with him on a professional and personal level, and I'm excited to welcome him into our group."
Inglis announced his retirement from the NRL in April 2019 after a series of injury concerns. Although he had 18 months remaining on his contract with the Rabbitohs, Inglis was paid out in full by the club despite not being medically retired.
"I just think it's time and I think it's the right decision for myself. I've come to terms with it," Inglis said last year.
"There has been a lot of speculation but as of today it's official. There are no regrets.
"It's not due to mental health or injuries, I just think it's the right time for me. I've been contemplating it for a while.
"That's me calling time on my career. No one else has called it.
"I'm happy with my decision. I get to work with the club and stay around Redfern and work with the boys and the community. My journey's only just starting now."