West Ham have confirmed the appointment of Sam Allardyce as manager with immediate effect.
Allardyce was first linked with the Hammers in January but the West Ham board opted to stick with Avram Grant for the remainder of the season.
Grant was sacked after West Ham's relegation to the Championship was confirmed with defeat to Wigan and despite Dave Jones and Neil Warnock both being linked with the vacant manager's position, co-owners David Gold and David Sullivan have turned to Allardyce.
"It is an honour to be the new manager of West Ham United. It is a fantastic club with a great tradition and loyal supporters who deserve to be in the Premier League. I can't wait to begin pre-season training as I am determined to get this club back where it belongs," Allardyce told the West Ham website.
"I wouldn't have taken this job if I didn't think we could bounce straight back into the Premier League. More than that, I wouldn't have contemplated the job if I didn't think there was the opportunity to build something substantial at West Ham."
Allardyce, who is currently on holiday in Spain, recently said he was looking forward to the challenge of guiding West Ham back to the Premier League and once he returns to London he will work closely with the West Ham board to shape his squad in preparation for the fight for promotion.
"There is a core of very talented young players at the club who've come up through the youth system, have West Ham in their blood and who I know I can build a successful team around," he added.
"That's what I'm looking forward to, managing a club that wins more games than it loses and competing at the top of the table. We need to create a winning mentality and give the fans a team they can be proud to watch.
"I know there will be West Ham fans asking whether I'm going to abandon the style of play that's been the club's heritage over the years. All I'll say is it will be a tale of home and away.
"At Upton Park we'll attempt to play the kind of passing game the fans want. We will aim to continue in the same way on our travels but we'll also be tough, hard to beat and utterly resilient."