Jonathan Sexton has completed his four-year deal to return to home club Leinster from Racing Metro next summer.
The British and Irish Lions fly-half has completed terms on a lucrative IRFU and Leinster central contract, in a clear boost to Ireland boss Joe Schmidt's Rugby World Cup 2015 preparations.
Sexton had been widely tipped to return to Ireland after his second year in France, and has now made good on the rumours.
The 29-year-old has struggled to settle in France and Ireland bosses were frustrated by their inability to control how frequently the 45-cap outside-half sees action at his Paris club.
"It's a choice for my family, my international career and my extended family in Ireland," said Sexton.
"I have a great rapport with everyone here, it was a very hard decision to make.
"I haven't spoken to any other French club other than Racing.
"Now, I don't want contract talk but to concentrate on Racing. I don't regret at all coming to France or Racing, it has been an incredible experience.
"I am pleased to be rejoining Leinster, the club where I started my professional career.
"I grew up playing my rugby in Leinster and always wanting to pull on the blue jersey so I am delighted to be able to return to play my club rugby in Ireland."
Sexton turned down a new long-term offer from Racing to complete his return home.
The prolific goal-kicker remains in a fitness battle for Ireland's autumn Test series after breaking his jaw in Top 14 action against Toulon.
Last season he was forced to play 13 games in 12 weeks after swapping Dublin for Paris, suffering a leg problem that threw his autumn series into doubt.
Sexton came through that scare, but that left Ireland head coach Schmidt determined to bring his sole frontline star operating abroad - and outside of IRFU control - back to home soil.
Sexton admitted last term that he was struggling to adapt to life in France and has now confirmed his impending Leinster return.
"Jonathan is one the best out-halves in world rugby and the IRFU are delighted that he will be playing his rugby in Ireland," said IRFU chief executive Philip Browne.
"Irish rugby will benefit hugely from having a player of his calibre playing full-time in Ireland."
Ireland will now hope that Sexton's return will nudge a host of out-of-contract stars to sign new deals to remain at the country's provinces next term, for the crucial run to the World Cup.
Leinster and Ireland were able to persuade the likes of Sean O'Brien and Jamie Heaslip not to follow Sexton's France switch last term.