Larsson joined Championship club Birmingham City on a season-long loan from Arsenal in August 2006, with an option to make the move permanent.
Larsson made an immediate impact, scoring late winners in his first few games, against Crystal Palace and Shrewsbury Town.
He also scored two goals against Newcastle United in the FA Cup.
At the end of January 2007, Larsson signed permanently for Birmingham City on a four-year deal for a £1 million fee.
He scored Birmingham's goal of the season, against Sheffield Wednesday in April 2007, running half the length of the field with the ball and finishing from inside the goal area.

In the 2006–07 season, Larsson was used mainly on the right wing, occasionally filling in at right-back or left-back when players were injured.
His performances on the wide right of midfield in the 2007–08 season, in particular a man-of-the-match showing against Bolton Wanderers, indicated this to be his best position.

Recalled to the starting eleven by new manager Alex McLeish for the game at Tottenham Hotspur in December 2007, Larsson scored a spectacular stoppage-time goal to give Birmingham their first away win in the Premier League for over three months.
He scored half of his six goals that season with direct free kicks, two in consecutive games, against Tottenham and Portsmouth, and one from 30 yards (27 m) against Liverpool.
With four weeks of the season remaining, Opta statistics rated Larsson as the most accurate taker of a direct free kick in the Premier League, though this ability failed to save Birmingham from relegation.

On the opening day of the 2010–11 season, Larsson recovered from what the Observer's reporter described as an "anonymous" start to provide assists for both Birmingham's goals as they drew 2–2 with Sunderland at the Stadium of Light.
He again provided an assist, this time for Craig Gardner, in his side's first home game, a 2–1 win against Blackburn Rovers.
Away to Fulham on 27 November, Alexander Hleb made "a terrific run" and a "slide-rule" pass to Larsson, who opened the scoring with his first goal of the season, a low shot across the goalkeeper.
The game finished 1–1.

Larsson played his part in Birmingham's run to the 2011 League Cup Final.
He scored from the penalty spot before Nikola Žigić headed an 84th-minute winner in the quarter-final against local rivals Aston Villa.
In the first leg of the semi-final against West Ham United, Liam Ridgewell scored from Larsson's corner before Victor Obinna was sent off for kicking Larsson in the groin in an off-the-ball incident.
Despite speculation over his future at Birmingham – with his contract due to expire at the end of the season, his advisor was given permission to talk to Newcastle United about a proposed move during the January transfer window, but personal terms were not agreed, and the player was booed when he came on as a substitute in the previous game, against Manchester United – Larsson returned to the starting eleven in place of the cup-tied David Bentley and played 100 minutes as Birmingham overturned a 2–1 deficit to win the semi-final 4–3 on aggregate.
Roger Johnson flicked on Larsson's corner for Žigić to give his team an unexpected lead in the final at Wembley against firm favourites Arsenal.
Though Robin van Persie equalised, Obafemi Martins scored an 89th-minute winner to give Birmingham their first trophy since 1963 in what the Daily Mail described as "the biggest upset at Wembley since Wimbledon beat Liverpool to the 1988 FA Cup."

Larsson took advantage of a defensive mix-up to open the scoring as Birmingham beat Sunderland 2–0 at St Andrew's on 16 April, and four days later, marked his 200th appearance for the club in all competitions with a penalty, albeit in a losing cause, against reigning champions Chelsea.
On 1 May, he exploited Michael Mancienne's mistake to score the equalising goal against Wolverhampton Wanderers, helping his side earn a point despite playing with ten men for more than an hour after Gardner was sent off.
No new contract was agreed, and following relegation to the Championship, the clu
Larsson joined Championship club Birmingham City on a season-long loan from Arsenal in August 2006, with an option to make the move permanent. Larsson made an immediate impact, scoring late winners in his first few games, against Crystal Palace and Shrewsbury Town. He also scored two goals against Newcastle United in the FA Cup. At the end of January 2007, Larsson signed permanently for Birmingham City on a four-year deal for a £1 million fee. He scored Birmingham's goal of the season, against Sheffield Wednesday in April 2007, running half the length of the field with the ball and finishing from inside the goal area.
In the 2006–07 season, Larsson was used mainly on the right wing, occasionally filling in at right-back or left-back when players were injured. His performances on the wide right of midfield in the 2007–08 season, in particular a man-of-the-match showing against Bolton Wanderers, indicated this to be his best position.
Recalled to the starting eleven by new manager Alex McLeish for the game at Tottenham Hotspur in December 2007, Larsson scored a spectacular stoppage-time goal to give Birmingham their first away win in the Premier League for over three months. He scored half of his six goals that season with direct free kicks, two in consecutive games, against Tottenham and Portsmouth, and one from 30 yards (27 m) against Liverpool. With four weeks of the season remaining, Opta statistics rated Larsson as the most accurate taker of a direct free kick in the Premier League, though this ability failed to save Birmingham from relegation.
On the opening day of the 2010–11 season, Larsson recovered from what the Observer's reporter described as an "anonymous" start to provide assists for both Birmingham's goals as they drew 2–2 with Sunderland at the Stadium of Light. He again provided an assist, this time for Craig Gardner, in his side's first home game, a 2–1 win against Blackburn Rovers. Away to Fulham on 27 November, Alexander Hleb made "a terrific run" and a "slide-rule" pass to Larsson, who opened the scoring with his first goal of the season, a low shot across the goalkeeper. The game finished 1–1.
Larsson played his part in Birmingham's run to the 2011 League Cup Final. He scored from the penalty spot before Nikola Žigić headed an 84th-minute winner in the quarter-final against local rivals Aston Villa. In the first leg of the semi-final against West Ham United, Liam Ridgewell scored from Larsson's corner before Victor Obinna was sent off for kicking Larsson in the groin in an off-the-ball incident. Despite speculation over his future at Birmingham – with his contract due to expire at the end of the season, his advisor was given permission to talk to Newcastle United about a proposed move during the January transfer window, but personal terms were not agreed, and the player was booed when he came on as a substitute in the previous game, against Manchester United – Larsson returned to the starting eleven in place of the cup-tied David Bentley and played 100 minutes as Birmingham overturned a 2–1 deficit to win the semi-final 4–3 on aggregate. Roger Johnson flicked on Larsson's corner for Žigić to give his team an unexpected lead in the final at Wembley against firm favourites Arsenal. Though Robin van Persie equalised, Obafemi Martins scored an 89th-minute winner to give Birmingham their first trophy since 1963 in what the Daily Mail described as "the biggest upset at Wembley since Wimbledon beat Liverpool to the 1988 FA Cup."
Larsson took advantage of a defensive mix-up to open the scoring as Birmingham beat Sunderland 2–0 at St Andrew's on 16 April, and four days later, marked his 200th appearance for the club in all competitions with a penalty, albeit in a losing cause, against reigning champions Chelsea. On 1 May, he exploited Michael Mancienne's mistake to score the equalising goal against Wolverhampton Wanderers, helping his side earn a point despite playing with ten men for more than an hour after Gardner was sent off. No new contract was agreed, and following relegation to the Championship, the clu
Sebastian Larsson