Ranger was rumoured to have agreed a deal to head to the Top 14 team in December of last year but an international recall led to rumours that he may decide to stay in New Zealand.
The 27-year-old put that speculation to bed in the summer and is now ready to begin a new chapter in the northern hemisphere after completing his ITM Cup duties with Northland.
"I'm both excited and nervous to start this new adventure," said Ranger, who arrived in Montpellier yesterday.
"I will have to learn about a new culture and a new way of playing rugby but I'm arriving here with a very open mind. I'm ready to meet new people and experience a new way of life and I'm very excited about that.
"I loved playing in New Zealand but I knew that at some point I would leave to go abroad. This is a good decision for me and my family. I was in advanced contact with Montpellier for a long time and I know that I will fit into both the city and the club."
Ranger featured for the All Blacks in their summer series with France but turned down a place in the Rugby Championship squad to focus on family life ahead of his Montpellier move.
He has had plenty of time to do his homework on what lies ahead and can't wait to play his part in a Montpellier side that he feels will suit his abrasive and entertaining style of play.
"I know that Montpellier are an ambitious club who want to win titles and produce an attacking game through their backline. That's something I will really enjoy," added Ranger.
"I watched all their games that I could back home on TV and, if that wasn't possible, I looked up all the information on specialised websites.
"Everything seems to be going pretty well for them at the moment (Montpellier are joint top of the French Championship) even if the team seemed a bit disappointed with the last few games."
Montpellier are currently one from two in this term's Heineken Cup, with an away win over Benetton Treviso followed by a disappointing defeat to Ulster on home soil.
That 25-8 reverse to the Irish outfit was their first loss at the Stade Yves du Manoir this season and it leaves their European hopes hanging in the balance ahead of the December double header with Leicester Tigers.
But Ranger's arrival and that of South African centre Robert Ebersohn will be a big boost for Montpellier boss Fabien Galthie and his troops.
Galthie also secured the signing of another former Springbok midfielder, Wynand Olivier, earlier this season and will welcome Wallaby lock Sitaleki Timani to the fold in time for the trip to Welford Road on Sunday, December 8.
Ranger and Ebersohn could make their debuts against defending champions Castres Olympique in the Top 14 on November 23, while Timani will join up with the squad after Australia's final autumn international against Wales a week later.