There is still much work to do if England are to reach their first World Cup final since lifting the trophy on home soil at Wembley in 1966.
But Southgate believes he has instilled the humble mentality in the dressing room that is required to keep the journey going all the way to Luzhniki Stadium next Monday (NZT).
Humility has replaced the hubris that defined the celebrity-obsessed David Beckham-era where the furthest the team reached was the quarter-finals of any tournament.
Just look back on how Harry Maguire, who headed in yesterday's first goal, reported for England duty for the first time last year with his clothing in a black trash bag rather than designer luggage.
Ambitions appeared to be thwarted for so long by a culture of entitlement as England gloried in the hype and status of being the birthplace of football without backing it up with results.
And as players started to collect millions in salaries from their clubs, commitment to the national team was called into question.
"We don't have renowned world-class players yet," Southgate said, "but lots of good young players who are showing on the world stage that they are prepared to be brave with the ball, try to play the right way, have shown some mental resilience now."
At the start of his tenure in 2016, Southgate realised he had to deliver an important message to his players: Any success with England will be greater than anything achieved with their clubs.
"They have been prepared to park their club rivalries at the door," Southgate said. "We've talked about how important it is to have that spirit."
Also, how to recover from adversity. One of the lowest points for English football came two years ago - days after that European Union referendum in Britain - when a team coached by Roy Hodgson was humiliated by Iceland.
"Under pressure, they suffered," Southgate said. "They will have days when they are not able to cope with things."
But experiencing the misery at Euro 2016 as players - or as a fan in the stadium like Maguire - helped a Harry Kane-led England advance relatively serenely to their first World Cup semifinal since 1990, according to Southgate.
England even managed to beat Colombia in the round of 16 on penalties, halting a run of five successive shootout losses at tournaments.
The victories in Russia are also reversing an anomaly. England hosts the world's richest football competition - the Premier League - but hasn't been able to produce a national team to match.
Southgate was in the last England side to reach a semifinal, at the 1996 European Championships, when the team anthem was Three Lions. The "football's coming home" lyric is back in vogue in Russia, ringing out from stadiums to bars among the few thousand fans who defied the logistical challenges and fears of corruption and violence to follow the team.
"We have a good balance and the team are together," 53-year-old England fan Andrew Court said outside the Samara stadium where Maguire and Dele Alli scored the goals against Sweden.
Southgate, though, is looking beyond the hollow "football's coming home" concept.
Reflecting a studious approach, the platform gained from his greatest day in football was used to deliver several powerful messages yesterday.
Above all, Southgate wants more Englishmen playing alongside the Premier League imports.
"The more remarkable thing is that we're in a semifinal," Southgate said. "We only have 33 per cent of the league to pick from. So that is still a huge problem for us, and we are playing some young players who are barely established at their clubs, never mind international careers.
"But we feel that they're able to play the way we want to play, playing with huge pride, playing with no lack of quality, showing the sort of mentality to work for the group," he said.
And it's a group that, Southgate emphasises, reflects the diversity of England and cuts through the economic divide in England where so much wealth is centred in the south.
Southgate has singled out the less affluent northern towns where players such as Maguire are from.
"All of these players come from different parts of the country," Southgate said, "and there will be youngsters watching at home from the areas they come from. They'll be inspiring."
Leading scorers
6
Harry Kane, England
4
Denis Cheryshev, Russia
Romelu Lukaku, Belgium
Cristiano Ronaldo, Portugal
3
Edinson Cavani, Uruguay
Diego Costa, Spain
Artem Dzyuba, Russia
Antoine Griezmann, France
Yerry Mina, Colombia
Kylian Mbappe, France
- AP