Tuchel will receive support from Anthony Barry, an English coach who previously collaborated with him at Bayern Munich.
"I am very proud to have been given the honour of leading the England team," Tuchel said in a FA statement.
"I have long felt a personal connection to the game in this country, and it has given me some incredible moments already. To have the chance to represent England is a huge privilege, and the opportunity to work with this special and talented group of players is very exciting."
Tuchel won league titles at PSG and Bayern and the German Cup with Dortmund, but his greatest success came during his time in English football at Chelsea.
He led the Blues to Champions League glory just months after taking charge in 2021 and also won the UEFA Super Cup and Club World Cup with the London club.
Tuchel was sacked in September 2022 in a bold early move by Chelsea's new ownership group that did not pay off.
Advertisement
He becomes the permanent successor to Southgate, who led the Three Lions to back-to-back finals of the European Championship, plus a World Cup semi-final and quarter-final in his four major tournaments in charge.
England, though, are still yet to win a major men's tournament since the 1966 World Cup on home soil.
“We are thrilled to have hired Thomas Tuchel, one of the best coaches in the world," said FA CEO Mark Bullingham.
"Since Gareth resigned, we have worked through the candidate pool, meeting a number of coaches and evaluating them against that criteria.
Advertisement
"Thomas was very impressive and stood out with his vast expertise and his drive."
Listen to the latest songs, only on JioSaavn.com
Tuchel will inherit a richly talented generation of players, including Harry Kane, Jude Bellingham and Cole Palmer, that will be among the favourites for the 2026 World Cup.
(This story has not been edited by staff and is auto-generated from a syndicated feed.)