The Denver Broncos are a professional American football team based in Denver, Colorado. They currently belong to the Western Division of the American Football Conference (AFC) in the National Football League (NFL). The Broncos began play in 1960 as a charter member of the American Football League and joined the NFL as part of the AFL-NFL Merger.

The Denver Broncos were a small-market team that met with little success in their early years but have since become one of the elite franchises of the league after having advanced to the Super Bowl six times. In their first four appearances, they suffered successively lopsided defeats, achieving near-legendary status as frustrated losers before winning back-to-back Super Bowl championships in 1998 and 1999 under quarterback John Elway, running back Terrell Davis and coach Mike Shanahan.

For most of their history they played in Mile High Stadium, which became one of the shrines of professional football for its record unbroken string of sell-outs and its legendary home-field advantage (often regarded as the best in the NFL) for the Broncos, especially during the post-season. Mile High Stadium was one of the NFL's loudest stadiums, with steel flooring instead of concrete, which may have given the Broncos an advantage over opponents. Since 2001, they have played at INVESCO Field at Mile High, built next to the former site of Mile High Stadium.

Although the Denver Broncos' 39-97-4 record was the worst of any of the original eight American Football League teams, the franchise had many proud moments and several AFL superstars, including Lionel Taylor and Floyd Little. The Broncos won the first-ever American Football League game over the Boston Patriots, 13-10, on September 9, 1960. They were the first AFL team ever to defeat an NFL team, on August 5, 1967 when they beat the Detroit Lions 13-7. Despite their relative lack of early success, the Broncos produced some memorable games, like the 38-38 tie against the Buffalo Bills in 1960.

Denver has reached the Super Bowl six times, winning it in the 1997 and 1998 seasons. It is odd to remember a time, then, when Denver was the lowliest of teams, managing its first winning season in 1973 after thirteen years of futility. Denver, in fact, came close to losing its franchise in 1965, but a local ownership group took control that year and began to build the team.

In 1967, under head coach Lou Saban, Denver took the field with almost two dozen rookies on its roster; though Saban's tenure was unsuccessful, it set the stage for later successes. In 1973, John Ralston coached the now-mature Broncos to a 7-5-2 record, including a dramatic tie with Oakland in Denver's first-ever Monday Night Football appearance that is still remembered as a pivotal game in Broncos history. Ralston coached the team until 1976, when well-publicized clashes between Ralston and his players led to Ralston's removal.

Rookie coach Red Miller, along with the Orange Crush Defense and aging quarterback Craig Morton, promptly took Denver to its first playoff appearance – and, ultimately first Super Bowl – in 1977, where they were defeated by the Dallas Cowboys, 27-10. Prior to 1977 season, Denver had received very little national attention and was rarely featured on nationally-televised games.

Quarterback John Elway arrived in 1983. Originally drafted by the Baltimore Colts as the #1 pick of the draft, Elway proclaimed that he would shun football in favor of baseball (he was drafted by the New York Yankees to play centerfield) unless he was traded to a selected list of other teams, which included Denver. Prior to Elway, Denver had had over 24 different starting quarterbacks in its 23 seasons to that point. Elway would remain the quarterback through five Super Bowls, three under head coach Dan Reeves and two under Mike Shanahan, and would end his career as the MVP of Super Bowl XXXIII, his last NFL game. The Broncos would lose Super Bowl XXI to the New York Giants 39-20, Super Bowl XXII to the Washington Redskins 42-10 and Super Bowl XXIV to the San Francisco 49ers 55-10, the most lopsided Super Bowl in history.

In 1995, the Broncos debuted rookie running back sensation Terrell Davis, who, in 1997 would finally lead the Broncos to their first Super Bowl victory, in Super Bowl XXXII, over the Green Bay Packers 31-24. Although Elway was unable to complete more than 11 of his 22 passing attempts, throwing one interception and no touchdowns, Terrell Davis was able to overcome a severe migraine headache that caused him blurred vision and rush for 157 yards and three touchdowns to earn MVP honors.

The Broncos repeated the following year, defeating the Atlanta Falcons 34-19 to win Super Bowl XXXIII. Since the Elway's retirement following the 1998 season, Denver has only had one losing season (1999) and has made the playoffs as a wild card three times (in 2000, 2003 and 2004), and as a division champion once (2005). However, they have won only one playoff game since Elway's retirement. Prior to the 2005 season, the Broncos were plagued by early season success followed by late season flops. In both 2003 and 2004 they started the season 5-1 and ended 10-6. In 2005, the Broncos would finally win a playoff game without Elway, defeating the defending Super Bowl champion New England Patriots, ending the Patriots 10 game playoff winning streak. Unfortunately, the following weekend, the hosting Broncos' were defeated at home by the visiting Pittsburgh Steelers in the AFC Championship by a score of 34-17.

Since the Shanahan era began, the Broncos have been known for having high-yardage running backs. Tuesday Morning Quarterback writer Gregg Easterbrook once mused that Denver’s helmets should have a label that says "Insert running back, gain 1,000 yards." To wit: Terrell Davis, Olandis Gary, Mike Anderson, Clinton Portis, and, Reuben Droughns have all posted 1000-yard rushing seasons in Denver, with Davis shattering the 2,000 yard barrier in 1998. In 2005, Mike Anderson rushed for more than 1,000 yards for the first time in five seasons. Anderson's backfield mate, Tatum Bell, fell 79 yards short of 1,000 with 921. That would have made them the first two running backs in over 20 years to break 1,000 yards in a single season on the same team.

So the debate rages on: is it Denver's system, or their running backs, that are responsible for the huge numbers year-in and year-out? Football Outsiders did a study to determine just that, and found some evidence that Denver's system of zone-blocking did aid running backs, and that most rushers who succeed in Denver will have a drop-off elsewhere. The study can be found here. It must be noted that both Droughns and Portis have had great success with their new teams after leaving the Broncos.