Patience has proved a virtue for Bamford, who was under consideration for a squad place in March and ahead of the Euro 2020 Championships earlier in the summer when he missed out on a place in the Three Lions’ provisional 33-man squad, with Ollie Watkins getting the nod instead.
The injury absence of Phil Foden and Marcus Rashford has now opened the door to Bamford.
The 27-year-old is part of England’s squad for a World Cup qualifying triple-header which kicks off with a Group I game in Hungary on September 2.
Three days later, England welcome Andorra at Wembley before visiting Poland on September 8.
On Bamford, who joins Leeds team-mate Kalvin Phillips in the party, Southgate said: “Phil Foden and Marcus Rashford were injured, so there was an opportunity in the forward areas.
“We were pleased with what Ollie (Watkins) did and now there is an opportunity for Patrick as a number nine.
“His progress with Leeds has been excellent, he was very close at the end of last season. We worked with him at Under-21 level, so we know him anyway. It is a special moment for his family.”
Bamford is the only uncapped player and there is no place for Bradford-born Mason Greenwood, but Trent Alexander-Arnold returns after missing Euro 2020 through injury.
Ex-Leeds loanee Ben White and Ben Chilwell went to the tournament, but are not included in a squad that welcomes back Jesse Lingard, who was cut from the provisional Euros group.
Nick Pope, who missed the tournament through injury, is picked ahead of ex-Sheffield United keeper Aaron Ramsdale.
Goalkeepers: Sam Johnstone (West Brom), Jordan Pickford (Everton), Nick Pope (Burnley)
Defenders: Trent Alexander-Arnold (Liverpool), Conor Coady (Wolves), Reece James (Chelsea), Harry Maguire (Man Utd), Tyrone Mings (Aston Villa), Luke Shaw (Man Utd), John Stones (Manchester City), Kieran Tripper (Atletico Madrid), Kyle Walker (Man City)
Midfielders: Jude Bellingham (Borussia Dortmund), Jordan Henderson (Liverpool), Jesse Lingard (Man Utd), Mason Mount (Chelsea), Kalvin Phillips (Leeds United), Declan Rice (West Ham)
Forwards: Patrick Bamford (Leeds United), Dominic Calvert-Lewin (Everton), Jack Grealish (Man City), Harry Kane (Tottenham), Bukayo Saka (Arsenal), Jadon Sancho (Man Utd), Raheem Sterling (Man City).