Conor Coady became Everton's fifth summer signing of 2022 on Monday.
The former Liverpool center-back moved to Goodison Park on a season-long loan from Wolves.
Everton had already completed deals for James Tarkowski, Dwight McNeil, Amadou Onana and Ruben Vinagre.
Coady's arrival bolsters Everton in defense after Ben Godfrey and Yerry Mina sustained injuries during Sunday's 1-0 loss to Chelsea.
Godfrey broke his leg and faces around three months on the sidelines, while Mina is set to see a specialist to assess the severity of his ankle ligament damage.
Coady had been a first-team regular at Wolves for the past seven seasons, serving as club captain in the last four.
But the 29-year-old was left out of Bruno Lage's starting XI on Saturday when Wolves fell to a 2-1 defeat at Leeds United.
Coady will be hoping that some good performances for Everton can earn him a place in Gareth Southgate's England squad for the World Cup in November.
He has been capped 10 times by the Three Lions to date, scoring one goal.
"It's incredible to join Everton," said Coady via the club's YouTube channel. "As soon as I heard the interest, from the manager but also the football club itself, I really wanted to be part of it straight away. I'm over the moon to join."
Coady spent almost a decade on the books of Everton's local rivals, having joined Liverpool's academy as a child. But he only made two senior appearances for the Reds before leaving to join Huddersfield Town in 2014.
"I've grown up around the city," he added. "I know the football club, how big this club is and what it means to the supporters. I'm someone who was desperate to come here, to play for this club. I've got family and friends who are massive Evertonians.
"I'm here to give absolutely everything I've got for this football club. It's important I work as hard as I can to help my team-mates, help the club move forward and make people proud."