The quarterback said on Twitter on Saturday he signed with the Hamilton Tiger-Cats, ending months of speculation on his possible path back to the game.
"Made the decision today to sign my contract with the CFL and further my football career after a long break," Manziel wrote. "Very grateful for everyone that's been supporting me along the way. I believe this is the best opportunity for me moving forward and I'm eager for what the future holds."
His last game came at the end of the 2015 season. He joins a team coached by June Jones, a former NFL and college coach. Players report to training camp this weekend.
In 2016, a domestic assault charge against Manziel in Dallas was dismissed after he took anger management course and participated in the NFL's substance-abuse program. In a recent interview, he said he's been diagnosed with bipolar disorder and has stopped drinking.
The CFL has a policy on violence against women and said in a statement that Manziel has met conditions to join the league. Those include an assessment by an independent expert on domestic violence, a review by legal counsel and a discussion with the commissioner.
Manziel was drafted out of Texas A&M by the Browns in the first round in 2014. He threw as many interceptions (seven) as touchdown passes during his two seasons.
In January, after signing a three-year contract to remain Hamilton's coach, Jones gushed about Manziel's potential.
"I think he'd be the best player to ever play up here," he said. "He can throw it and he can run it like nobody ever has been able to do."
Hamilton (6-12) finished third in the East Division last year and missed the CFL playoffs. The Ticats were 0-8 with quarterback Zach Collaros before Kent Austin resigned as coach and was replaced on an interim basis by Jones.
The Ticats signed quarterback Jeremiah Masoli, who went 6-4 after being named Hamilton's starter by Jones, and receiver Brandon Banks to contract extensions in January.