Roger has been capped at A International level and has one senior cap won on Ireland's 2005 tour to Japan.
"While the back row is already a competitive area, the addition of Roger to the squad will provide us with the depth we need to ensure we are competitive in both the RaboDirect PRO12 and the Heineken Cup." commented Ulster's Director of Rugby David Humphreys
"He displays all the physical attributes necessary for a top-class No.8 and is an incredibly consistent performer. He's currently playing the best rugby of his career and we're delighted that he has decided to return to Ulster next season and to commit his long term future to the club."
Wilson has appeared over 100 times for Northampton and is one of the club's most consistent performers.
"I've really enjoyed my time at Northampton and the club have been very good to me" he commented.
"Dorian West is an excellent forwards coach, Jim Mallinder's knowledge of the game is outstanding and I'd like to think that I've learnt a lot from them over the last four years and I can add that experience to Ulster.
Northampton are a quality team and have an excellent set-up at the club but I suppose it was always in the back of my mind that I would like to finish my career at Ulster. I was born and raised there, learnt my rugby there and at the end of the day it is home. I'm delighted to be coming back.
The last couple of seasons have shown that Ulster are a club that can compete and compete to win things, they're now considered one of the top European teams and that they're genuine contenders for silverware.
Ulster have a lot of strength and depth in the squad now, particularly in the back row. They don't just rely on picking a strong 1st XV but have excellent players who can back up those who are starting a particular game and can make an impact from the bench. That is a very important thing for a squad, it keeps everyone competing for places and ensures no-one is complacent."
During his time at Northampton Wilson met his former team just once, in last season's Heineken Cup quarter-final at the Stadium:MK, and admits it was a day of mixed feelings;
"It was a strange day, I wouldn't particularly describe it was enjoyable. After the whistle went it was great to catch up with the Ulster boys but I had mixed feeling. I certainly wanted to do my best and give 110% for Northampton, but given that during my time with Ulster we'd been striving to reach the knockout stages of the Heineken Cup, and I suppose there was a little bit of envy on my part that I wasn't part of the Ulster squad on the day."
Roger Wilson Stats
DOB: 21st Sep 1981
Height: 1.88m (6'2)
Weight: 106kg (16st 9lb)
Position: No.8
Honours: Ireland (1 cap)