None of the moves were surprising, and more are expected.
The Jets decided to keep their coach, Rex Ryan, but fired General Manager Mike Tannenbaum. The Browns made it a clean sweep, dismissing General Manager Tom Heckert along with Shurmur. Reid was the longest tenured of the group, let go after 14 seasons with the Eagles.
Gailey was dumped after three seasons with the Bills, Shurmur after two in Cleveland and Crennel was coach of the Chiefs for one full season.
Jacksonville fired General Manager Gene Smith.
In Philadelphia, the Eagles owner Jeffrey Lurie said it was time "to move in a new direction."
The dismissal came one day after Reid and the Eagles were humiliated, 42-7, by the Giants and ended their season at 4-12.
"Andy leaves us with a winning tradition that we can build upon. And we are very excited about the future," Lurie said in a statement released by the team.
Reid took over a 3-13 team in 1999, drafted Donovan McNabb with the No. 2 overall pick and quickly turned the franchise into a title contender.
He is the winningest coach in club history and led it to a run of four straight N.F.C. championship games, a streak that ended with a Super Bowl trip after the 2004 season — and a loss, 24-21, to the New England Patriots.
Still, Reid cemented Philadelphia as a football town — though the Eagles have never won the N.F.L. title — and led the team to an unmatched level of success. But the team has not won a playoff game since 2008, and after last season's 8-8 finish, Lurie said he was looking for improvement this year.
Instead, it was even worse.
In Ohio, the Browns began what is expected to be a massive off-season overhaul by the new owner Jimmy Haslam. Shurmur was 9-23 in his two seasons with the Browns, who will embark on yet another off-season of change — the only constant in more than a decade of futility. Cleveland has lost at least 11 games in each of the past five seasons and made the playoffs just once since returning to the N.F.L. as an expansion team in 1999.
Shurmur's replacement will be the Browns' sixth coach since 1999.
While the Chiefs fired Crennel, they made no move on the embattled general manager Scott Pioli despite a 2-14 season marked by blowout losses, fan rebellion and a murder-suicide involving one of their players.
Crennel was fired after one full season as coach, and one day after Kansas City matched the fewest wins in franchise history with an embarrassing 38-3 loss to the Denver Broncos.
"I am embarrassed by the poor product we gave our fans this season, and I believe we have no choice but to move the franchise in a different direction," Chiefs chairman Clark Hunt said in a statement. "I will immediately begin the search for the next head coach of the Chiefs. The entire football operation will remain under review and there may be additional changes to come."
Hunt said that "no final determination has been made" about Pioli's future.
The Chiefs' only victories this season came against New Orleans and Carolina, the latter coming one day after linebacker Jovan Belcher shot his girlfriend to death and then drove to the team's practice facility and turned the gun on himself as Crennel and Pioli looked on.
Crennel seemed to know the end was coming Sunday night when he was asked to defend his job and said, "If your criteria is wins and losses, there's not much defense."
The Bills fired Gailey after three losing seasons. They closed out another disappointing season Sunday with a 28-9 win over the Jets.
Buffalo finished 6-10, and Gailey leaves with a 16-32 record. There was no immediate word on the status of General Manager Buddy Nix.
In a hopeful season after signing star defensive end Mario Williams to a $100 million contract, the Bills reverted to their ways of the past, failing to make the playoffs for a 13th straight year, the N.F.L.'s longest active drought.
Gailey also announced that his entire staff had been fired.
"I understand this is a business. We didn't get the job done," Gailey said, reading from a Bills pad on which he had jotted down a few notes. "I've been called two other times to get things turned around, was able to do it. We weren't able to get this one done soon enough and I understand that completely."
Gailey's eyes then welled with tears when he credited Bills fans for their loyalty, and Buffalo for being a passionate football city.
"I think that the next staff will have a great opportunity for success, and make this another great football franchise," Gailey said. "This will probably be, and I say probably, but I think it will be the first place that's ever fired me that I'll pull for."
Gailey had at least one more season left on his contract.
