The 30-year-old joined London Irish after playing provincial rugby for both Munster and Leinster. He was also a vital part of the team that beat Saints in the Powergen Cup final in 2002.

Everitt said: “I see this an opportunity to develop my game under a head coach like Paul Grayson, who I have a lot of respect for having played against him many times and I can completely appreciate his extensive knowledge of the game,

“This was a difficult decision for me having spent so many years with London Irish but having come to Franklin’s Gardens as an opposition player, I was always aware of the great sense of loyalty and camaraderie among the supporters; a similarity that is shared with the club I am coming from and at Munster.

“However, it was not until I came here and spoke with the management and players like David Quinlan that the club really appeared to be just as I had expected. Northampton is also a club that is steeped in history, is a past Heineken Cup winner, has been a major force in Europe for many years and has the best facilities I have seen in the Premiership.

“This is quite a commitment for me as it will probably be my last long-term contract. I look forward to the challenge ahead and being part of something special as Saints move forward.”

Everitt, married to Lisa and father to Juliette, aged two, and nine-month-old Ella, added: “I also want to give something back on the field and if that means helping out younger players like Stephen Myler by using my Premiership experience then I am keen to do so.”

Head coach Paul Grayson said today: “Barry is a proven performer over a number of years and has great experience in the Premiership. His kicking game obviously stands out as exceptional, however he is a very capable footballer and distributor and there is a lot more he has to offer. I am looking forward to working with him to express his full range of talents.”

Saints' chief executive Allan Robson said: "Barry's signing means we have been able to strengthen our backline and secure one of the most prolific goal-kickers of recent times in one move. We are delighted to have managed to secure his services."