The French winger has returned to his homeland to link up with Guingamp on a season-long agreement.
The 28-year-old, who has spent the last three years in England, hopes to find regular game time back in Ligue 1.
The former Rennes midfielder was restricted to just nine Premier League outings in 2013/14 as Newcastle manager Alan Pardew favoured other options.
Marveaux says it is that lack of action which has forced him to look elsewhere, commenting: "I wanted to leave Newcastle United to play more football. I need to play."
Guingamp are happy to offer Marveaux the opportunities he craves, with club president Bertrand Desplat admitting that a permanent deal in 2015 is a distinct possibility.
He said: "It is the return of the Prodigal Son for us. I was dreaming of getting someone like Sylvain back in the team. He is from Brittany and we are all moving in the same direction.
"He didn’t fulfil his potential with Newcastle because he was not playing there.
"At Guingamp we believe he will fulfil his potential because he will be playing more games.
"I would like to thank Newcastle. The negotiations were difficult but we got there.
"It's a transfer with an option to buy permanently. We will decide at the end of the season if we want to take up the option."