Saliba joined Arsenal in the summer of 2019 from Saint-Etienne for £28million, but he then spent the next three years out on loan.
The centre-back finally returned to Arsenal this summer and Arteta has revealed the 21-year-old swiftly won him over.
Saliba has gone on to start every Premier League game this season and the Gunners are five points clear of Manchester City at the top of the table.
“The first question was how the player is going to reintegrate into our dynamic after being out for so long,” said Arteta.
“Is there some frustration there, something personal between, for example, between me and the player because he could not understand that?
“Or his environment, his expectations coming back or the amount that we paid for him, his age, is it the same to do it in France as it is to do it in this League for Arsenal because you don’t have 21-year-old defenders at the top level in England?
“There were a lot of question marks and he went with all of them, ticking them off and giving us every reason to be confident that he was a great player for us.”
Arteta has not only been impressed by Saliba’s adaption, but how quickly he has made an impact in England.
“For the first week I didn’t speak to him,” said Arteta. “I just wanted to see – naturally, without me really interfering in his thoughts – how he was. Because then you can understand the real him and after that I spoke to him.
“His attitude, the way he came in and said: ‘I’m going to prove that I’m very good and I deserve to be here.’
“Without any looking back or being shy, he was doing it the right way and giving the right reasons to think that he was going to be really good for us.
“He had an immediate impact. The first two training sessions that we looked at home we went: ‘There’s huge potential here’.
“He took out every question mark that we could have with him and gave us all the reasons to play him. And I think he’s been exceptional since that day.”
Despite not playing for Arsenal during his first three years at the club, Saliba was hugely popular among the fans.
The defender’s performances on loan caught the attention of supporters and clips of his displays often went viral on social media.
“I was 100 per cent sure that I was going to have a lot of pressure externally to give him the opportunity – that was for sure,” said Arteta.
“And obviously I was really willing to find out what we found out in pre-season. Then it was the perfect storm and a beautiful relationship started to build there.
“He’s really funny, and he doesn’t want to be funny. He’s really liked around the place. He’s good, he has his aura and presence and always the humour and energy around him. And then he is very focussed and determined to become a top player.
“I have to be fair with myself, I have to put players that I feel can do the role, especially in that role in defence.
“But I was hoping it was the right decision and the decision we took – against probably a lot of opinions – to send him another year on loan, paid off.
“And that it was the right timing now to bring him back. But I have questions that I could be totally wrong as well.”