Southgate took over in 2016 and brought more success to the national than they'd had since they won the World Cup in 1966.
After reaching the World Cup semi-finals in 2016, the Three Lions then went one step further at Euro 2020, losing the final to Italy on penalties.
That was followed by a quarter-final exit at the 2022 World Cup before Southgate led his side to the Euro 2024 final this month.
They once again fell at the final hurdle, being beaten 2-1 by Spain, and that proved to be the last match of his tenure.
"As a proud Englishman, it has been the honour of my life to play for England and to manage England. It has meant everything to me, and I have given it my all," Southgate said in a statement.
"But it’s time for change, and for a new chapter. Sunday’s final in Berlin against Spain was my final game as England manager."
Southgate divided opinion in the final stages of his time in charge, frustrating many with the pragmatic football he played with a squad full of attacking talent.
Not even a run to the final of the Euros silenced the doubters, with that run consisting of narrow wins over sides that many felt England should have beaten comfortably.
Nevertheless, there's no denying that the former player transformed a national team that had previously failed to get past the last eight of a major tournament in over a decade, and will go down in history as one of their best managers.
"I have had the privilege of leading a large group of players in 102 games. Every one of them has been proud to wear the three lions on their shirts, and they have been a credit to their country in so many ways," he added.
"The squad we took to Germany is full of exciting young talent and they can win the trophy we all dream of. I am so proud of them, and I hope we get behind the players and the team at St. George’s Park and the FA who strive every day to improve English football, and understand the power football has to drive positive change.
"My special thanks go to the backroom staff who have provided the players and me with unstinting support over the last eight years. Their hard work and commitment inspired me every day, and I am so grateful to them – the brilliant ‘team behind the team’."
England's CEO Mark Bullingham also had his say on Southgate's departure.
"In the 25 tournaments post 1966 before Gareth took charge, we had won seven knockout games," England FA CEO Mark Bullingham said.
"In his four tournaments we have won nine. So, in his eight years, he has won more games that really matter than in the previous 50 years."