The Scotland international was confirmed as a Dons player on Sunday afternoon, joining from Hamburg on a three-year deal.
Bates had interest elsewhere with Hearts strongly linked with a move for the player ahead of signing Taylor Moore from Bristol City.
The 24-year-old had been frozen out at the German second tier side.
“It feels great,” he AberdeenFC/ status/1431979080342253578">told RedTV. “I thought it was really important for me to try and settle somewhere and enjoy football somewhere, kick on and hopefully have a good few years.
“I knew the interest quite early on. I had interest in Scotland.
"I spoke with the manager. I’ve heard really good things about him. What he said to me about how he wants to play it really suits me down to a tee as well. It was a big pull.”
Bates, who has been capped four times for Scotland, played 28 times for Hamburg after joining from Rangers.
In the last two seasons he has had loan spells with Sheffield Wednesday, which lasted one game after suffering a season-ending injury, and Belgian top-flight side Cercle Brugge.
“A lot to be fair,” he said when asked how much he has improved as a player.
"I went over there the first year and played a lot, changed as a player. People I speak to say I've got a lot better and changed my game a little bit.
"Hopefully I can show that in the games coming up.”