Smith had also targeted Chelsea’s Ruben Loftus-Cheek as an alternative loan signing, but Barkley was always Villa’s priority and a deal was completed on Wednesday morning.
Barkley was an unused substitute in Chelsea’s defeat to Tottenham in the Carabao Cup and admitted that regular football with Villa persuaded him to make the move.
“The Euros was a big influence for me coming here because for the last couple years it has been stop-start for me [at Chelsea], performing and then being out of the team,” he said.
“To come here and have the chance to play and perform regularly was a big thing for me and with the Euros at the end of the season it’s a target of mine to be in the squad and hopefully be there.
“Villa know my strengths and what I can add to the team. It’s a massive club and it looks like it’s going to be an exciting season. Hopefully we can improve this season compared to last season.”
Barkley will be ineligible for Villa’s Carabao Cup tie at home to Stoke on Thursday night but will be available for the Premier League game against champions Liverpool this weekend.
Loftus-Cheek, meanwhile, is still likely to be allowed to leave Chelsea on loan before the transfer window shuts, but his options may be limited.
Although a number of clubs have shown a strong interest in Loftus-Cheek, many have been scared by his £150,000-a-week wages and his injury record.
Fulham are one of the clubs interested in Loftus-Cheek, but any move from Chelsea’s neighbours may depend on whether or not they can sign defenders on permanent deals.