The 20-year-old defender recently revealed he turned down the opportunity to join the Europa League champions in the January transfer window, preferring instead to continue playing regular football with FC Nordsjaelland.
Now it has emerged that Chelsea renewed their interest again at the end of the season, only for the Denmark international to reject the chance to link up with Jose Mourinho at Stamford Bridge, opting for a four-year contract at Villa Park instead.
"I have a good feeling it was the right decision to turn down Chelsea," said Okore. "I feel that I have arrived at a club that believes in me.
"The manager has said all the right things and that has caught my attention. This is going to be good."
With Nordsjaelland, Okore won the Danish Cup in 2011 and the league title in 2011/12 and featured in the Champions League group stage last season.
He made his debut for the Danish national team in November 2011 and has won seven senior caps since.
The Ivory Coast-born centre-back also attracted attention from Manchester United in the past, after a series of impressive performances for club and country, but has decided to embark on his Premier League career with Aston Villa.