Chairman Steve Hollis has branded Aston Villa's disastrous Premier League campaign as "unacceptably fractured both on and off the pitch".
Villa's relegation to the Championship was confirmed on Saturday as Marcus Rashford secured a 1-0 win for Manchester United at Old Trafford.
It completed a miserable season for Villa - who have played in every Premier League campaign since its inception in 1992 - that has seen Tim Sherwood and Remi Garde both fail to turn around their flailing fortunes.
Villa's fans have regularly protested against the club's owner Randy Lerner for their fall from grace and that continued against United, but it was unable to stop them slipping out of the top flight with four games remaining.
"First, on behalf of the board, let me express my deep regret that I find myself writing this open letter to you, knowing just how much hurt and pain, anger and anguish will have been felt by you all after the club lost its Premier League status this weekend," Hollis said in a statement published on Villa's official website.
"Your profound sadness is shared by everyone connected with the club and while I know that will be of little consolation in the days ahead, it should be a source of reassurance as we rebuild the foundations for future successes.
"We must acknowledge that this weekend's confirmation has been the culmination of an unacceptably fractured season both on and off the pitch. That isn't down to bad luck. To make such a claim would be insulting to each and every one of you. I must add you have all displayed unyielding commitment in adversity."
However, Hollis - who was appointed in January - has vowed to inspire change at Villa Park, starting with the recruitment of their next permanent manager.
He added: "While it is of little solace at present, the process of identifying the root causes of our circumstances started long ago and the focus now has to be looking forward and making sure lessons have been learnt.
"The search for a new manager to provide drive, direction and immediate promotion has commenced.
"Together, we share the same goal. We intend to restore Aston Villa Football Club to its rightful place. It is a journey we must make together so we can bring success, enjoyment and exciting football back to Villa Park once more."