Born and raised in England, Morgan chose to represent Jamaica at international level, making his debut for them in 2013 and was part of their teams that competed in two Copa América tournaments and finished runners-up at the 2015 CONCACAF Gold Cup.

[8] In February 2003, with manager Paul Hart considering him close to a first-team breakthrough after his reserve performances, Morgan was loaned to Kidderminster Harriers of the Third Division.

[9] He made his professional debut on 1 March, playing the full 90 minutes of a 3-1 loss to Scunthorpe United at Aggborough, deflecting a 25-yard Peter Beagrie shot for the first goal.

[10] Morgan totalled five appearances for the Worcestershire side, scoring his first goal two weeks after his debut, heading to confirm a 2–0 victory at Cambridge United.

[8] He made his debut at left-back on 12 August 2003 away to Port Vale at the age of 19; after a goalless draw, Forest won a penalty shoot-out to advance to the second round of the League Cup.

[8] On 18 October, he scored his first goal for Forest, heading Eoin Jess' cross to finish a 6–0 win over bottom team Wimbledon at the City Ground.

Morgan found it hard adapting to life back in the Championship during the first half of the 2008–09 season, with Forest languishing in the relegation zone by Christmas.

Following the dismissal of Colin Calderwood on Boxing Day 2008, and the arrival of Billy Davies soon after, Morgan and the Forest defence looked far more solid as the season progressed which eventually led to the Reds retaining their Championship status.

[15] On 30 January 2012, Morgan joined East Midland rivals Leicester City for an undisclosed fee believed to be in the region of £1 million.

On 3 April 2016, he scored the only goal against Southampton,[22] despite feeling ill.[8] On 1 May, he equalised with a header in a 1–1 draw with Manchester United at Old Trafford, and the next day Leicester won the title, with Morgan becoming the first Jamaican to win a Premier League medal.

[23] After captaining Leicester City to the title, Morgan was included in the Premier League PFA Team of the Year, alongside teammates Jamie Vardy, N'Golo Kanté and Riyad Mahrez.