Colchester

Until 1937, Colchester Town were Colchester's main club and were the original tenants of Layer Road. Colchester Town joined the Eastern Counties League in 1935, but their poor performances in the league convinced supporters that the club should turn professional, much like nearby Ipswich Town. With club officials against the idea of turning professional, a new professional club was formed in March 1937, Colchester United, which would also play at Layer Road. United joined the Southern Football League as crowds for Town matches dwindled. In December 1937, Colchester United formed a reserve team, signing many of Town's players. As a result of this and Town struggling with £300 debts, Colchester Town folded the same month.

The club were Southern League champions in 1939 prior to the Second World War. Following the war, in 1947–48, the U's produced one of the most notable FA Cup runs by a non-league side, defeating fellow non-leaguers Banbury Spencer in the first round, before beating Football League clubs Wrexham, Huddersfield Town and Bradford Park Avenue. They finally fell to Blackpool in the fifth round. This set them in good stead for potential election to the Football League.

Colchester United were elected to the Football League in 1950 on the back of their second Southern League Cup win and ending the 1949–50 season second to Merthyr Tydfil on goal average alone. They spent eleven years in the Third Division South and Third Division following the league's reorganisation, with a best finish of third place in 1957, just one point behind rivals Ipswich Town and Torquay United.

The club suffered their first relegation in 1961 as they finished 23rd in the Third Division, but didn't have to wait long until their first Football League promotion, spending just one season in the Fourth Division as they ended the season second to Millwall by just one point. This trend continued over the next two decades as they were relegated to the Fourth Division in 1965 and promoted to the Third Division in 1966, then relegated in 1968 and promoted in 1974, relegated in 1976 and promoted in 1977 before a final relegation to the Fourth Division in 1981.

During this time, the club embarked on one of the most notable runs in FA Cup history, as manager Dick Graham took his ageing side to the 1970–71 quarter-finals, dispatching non-league Ringmer, Cambridge United, Barnet and Rochdale following a replay. With the draw having been made prior to the replay against Rochdale, the U's knew they would face a home tie with First Division Leeds United, and duly trounced Dale 5–0. In the match with Leeds, the U's raced to an unprecedented 3–0 lead in front of a 16,000 Layer Road crowd, with two goals from Ray Crawford and one from Dave Simmons. Leeds did grab two goals back but Colchester held on for a famous 3–2 victory. The club faced Everton in the quarter-finals but succumbed to a 5–0 defeat in front of 53,028 at Goodison Park.

Financial difficulties and a number of changes at board level in the mid-1980s caused a slide towards the lower end of the Fourth Division table and crowd numbers to dwindle. Despite a brief turn around in form under former Rangers manager Jock Wallace, United were relegated from the Football League for the first time since their election.

Despite their relegation, the U's remained a full-time club while playing in the Football Conference, as they sold their Layer Road ground to the Colchester Borough Council to clear the club's debts. The club finished the season as runners-up to Barnet during their first season outside of the Football League, but, under the stewardship of player-manager Roy McDonough, the U's won the league the following season on goal difference over bitter rivals Wycombe Wanderers. In addition to earning a swift return to League football, the club also won the FA Trophy in 1992.

The club had a successful 1995–96 season as they reached the 1995–96 Football League play-offs, but were defeated by Plymouth Argyle at the semi-final stage. The club narrowly missed the play-offs in 1996–97 but did however reach the Football League Trophy Final held at Wembley. The U's drew 0–0 with Carlisle United but were defeated 4–3 on penalties. The following season however, Colchester were promoted via the Third Division play-off final with a 1–0 Wembley win against Torquay United.

Colchester consolidated their position in the third tier of English football for a number of seasons, before achieving their then-highest league finish of second place only to Essex rivals Southend United in the 2005–06 season. Under Phil Parkinson's stewardship, the U's were promoted to the second tier for the first time in their history. However, when Parkinson left to take the reins at Hull City, his assistant Geraint Williams was handed the daunting task of guiding Colchester into their first season in the Championship. He led the side to a 10th position finish, above East Anglian rivals Ipswich Town, Norwich City and Essex rivals Southend United, while gaining the Pride of Anglia title in the process for the first time in their history. The momentum however did not continue into their second season in the Championship, as they finished bottom of the league and were relegated back to League One.

During the club's second season in the Championship, Layer Road hosted its final game on 26 April 2008 as the U's fell to a 1–0 defeat to Stoke City. The club then moved to their new ground, the Colchester Community Stadium, in the summer of 2008 in preparation for life back in the third tier. Despite hoping to make an immediate return to the Championship, the club made a dreadful start to the 2008–09 campaign, which saw manager Geraint Williams lose his job, leaving the club second from bottom. He was replaced by former Wycombe Wanderers manager Paul Lambert as he guided the club to a mid-table finish.

Colchester United started the 2009–10 season by thrashing recently relegated Norwich City 7–1 on the opening day of the season at Carrow Road. Manager Lambert then defected to Norwich when their manager Bryan Gunn was sacked following a poor start to the season. This ensured a fiery return fixture, held at the Community Stadium in January 2010. The game saw a record crowd of 10,064 watch as the U's fell to a 5–0 defeat, with Ian Henderson being sent off on his United debut against his former club. The season ended with Colchester finishing in 8th position. The club finished in 10th position for both the 2010–11 and 2011–12 seasons, before narrowly avoiding relegation to League Two in the 2012–13 season, defeating Carlisle United 2–0 on the final day of the season to ensure their safety. The club then finished the 2013–14 season in 16th position.

Colchester secured League One safety on the final day of the 2014–15 season when they beat promotion hopefuls Preston North End 1–0 on 3 May 2015. However, Colchester could not stave off relegation to League Two in the 2015–16 season as they finished the campaign in 23rd position, confining them to the fourth tier of English football for the first time in 18 years.

In the 2019–20 EFL Cup, Colchester defeated Premier League side Tottenham Hotspur on penalties. Colchester were eventually eliminated by Manchester United in the quarter-finals, losing 3–0 at Old Trafford.