Bartley wants to repay Ally McCoist for his faith in him after his injury problems by helping the new boss retain the title.
The on-loan Arsenal ace told the Scottish Sun: "I gave the boss my word last season that I'd be back and I'm glad to be here.
"I don't think the boss needed to change much.
"We had a great manager in Walter Smith and Ally has just kept that going.
"It's a fantastic club and it's a good place to learn. I'd say we look stronger than last year.
"We're undefeated for the season, the team spirit is good with a good manager and hopefully we can keep it going."