The former Manchester United striker made a permanent transfer to OM yesterday.
He told La Provence: "Why did I choose OM? Marseille is a very big club in France, perhaps the biggest. It's the only one to have won the Champions League in 1993. It is a club with a great history, an incredible crowd and I have had good talks with the new manager, Roberto De Zerbi, I know a little from having seen his team, Brighton, play in the Premier League.
"He was a very important factor. He has very precise tactical ideas, I watched a lot of his team's Premier League matches and Brighton were a very pleasant team to watch. I'm really looking forward to starting this new adventure under his command."
Of leaving the controversies of last yeat behind him, Greenwood added:"I am aware of all this, obviously, but I don't want to get into any controversy. I had already expressed my feelings last year.
"Today all this is behind us: my partner (Harriet Robson) and I have rebuilt ourselves as a couple. We have been together since we were 16, we have a wonderful little girl. We look forward and can't wait to start this adventure in Marseille."