Barca paid an initial €45million to sign Lewandowski from Bayern, where he had one year left on his contract and had made his desire to leave clear after a breakdown in talks over an extension.
Lewandowski denied wanting out because of the Bundesliga champion's reported interest in Erling Haaland, who ended up swapping Borussia Dortmund for Manchester City.
While he was unwilling to give the full details, he hit out at his former club for painting what he feels was an inaccurate portrait of the situation.
"No, that was nothing to do with Erling," he told ESPN FC. "I am the guy who even if something's not good for me, truth is more important.
"I don't want to speak about what happened exactly. But if the question is if the decision to move was because of him, no, I didn't see the problem if he joined Bayern Munich.
"But some people don't tell me the truth, [they] say something different. And for me, it was always important to be clear, to stay true, and maybe for a few people that was the problem.
"In the end, I know that something doesn't work well with my person... and I feel that maybe it's a good time to move out of Bayern Munich and join Barcelona.
"I had a very good relationship with my team-mates, with the staff, with the coach, and these are all things I'm going to miss because I spent a beautiful time there.
"We were not only friends from the pitch but also something more. But in the end this chapter is over, and I open a new chapter in my life and a new chapter in my career.
"So I feel that I'm in the right position, right place. So everything that's happened in the last few weeks before I left Bayern Munich, that was also of course a lot of politics.
"The club tried to find an argument [for] why they can sell me to another club because before it was difficult to explain maybe to the fans. I had to accept that, even though it was a lot of bulls***, a lot of s*** said about me.
"[It was] not true, but in the end I knew that the fans, even in this period, still support me a lot."