The manager credits his team's attitude after reaching the top four ahead of Tottenham with a final-day win over Newcastle - the club's eighth in an 11-game unbeaten run.
The Gunners had opened March with a 2-1 defeat away at its north London rival that left the club off the pace in fifth, but went on to win eight of the final 10 league games.
Sunday's win meant that Wenger's side qualified for the Champions League, despite a year in which the club endured a run of one win in six matches beginning in November as well as humiliating exits to Bradford City and Blackburn in the Capital One Cup and FA Cup, respectively.
After Sunday's victory at St James's Park, Wenger told Sky Sports: "I'm proud of the character and the spirit from these players, after all we had to deal with the season. They are special. I said that many times but they have shown it - in the last two months they have been exceptional.
"It's a good basis for the longer term to go into next season following such a strong run and I'm proud given we were very far behind Tottenham after the defeat there.
"Everybody ruled us out but we have shown character and attitude and came back. We reached 73 points – that's three points better than last season."
Asked if he now felt vindicated following the criticism he endured at various points during the season, Wenger replied: "No. I just did what I feel is right because these players deserved it. I had many groups in my life and the focus, the desire to do well was always exceptional.
"It's one of the best groups I've ever had in my life on that front and their combination of quality and attitude has been great."