Some do it because they've moved, some do it just to re-brand, and others have more questionable motives. These are the 13 NBA teams out of the current 30 that have, at some point, changed names.
1) New Orleans Pelicans (Hornets)
2) Charlotte Hornets (Bobcats)
The name Hornets made its debut as an NBA moniker in 1988, but it was first applied to the city of Charlotte during the Revolutionary War. That's when British commander Lord Cornwallis labeled Charlotte as a "veritable hornet's nest" due to its stubborn resistance to military force. If original owner George Shinn had his way, his team actually would have been called the Charlotte Spirit but Hornets luckily won out in a fan voting contest. Though the team was wildly popular in the '90s with a bevy of young stars and their signature teal jerseys, the franchise sputtered in the '00s. When Shinn, who had recently been accused of sexual assault, lobbied city officials for public funding for a new arena in 2002 and was summarily rebuffed, he quickly relocated the franchise to New Orleans but kept the Hornets name. Commissioner David Stern promised he'd bring a new franchise back to the area swiftly, and sure enough the Bobcats started play just two years later. Both the team name (which supposedly won out in fan voting, but was obviously the preference of owner Robert "Bob" Johnson) and the product on the court became a subject of scorn, with the Bobcats reaching the playoffs just twice in their first 10 years, both first round losses. Meanwhile, the New Orleans (and sometimes Oklahoma City) Hornets were struggling financially in the wake of Hurricane Katrina and after Shinn hoisted the franchise on the league to cut his losses, it was soon sold by the NBA to Saints owner Tom Benson. Seeking a fresh start, Benson vacated the Hornets name to rebrand as the New Orleans Pelicans, a bird native to the Mississippi River delta. In one of the few savvy moves he's made since taking over team ownership from Johnson, Michael Jordan then applied to change his team's name from Bobcats to Hornets, which took effect in '14-'15. The official franchise history is now a little confusing, as the NBA declared that the Hornets are a franchise that started in 1988, disappeared from 2002 to 2004, were named the Bobcats from 2004 to 2014, and are now the Hornets again since 2014. Meanwhile, the Pelicans were declared as a new franchise called the New Orleans Hornets starting in 2002, that changed its name to the Pelicans in 2013. There was no concern over where a championship banner would hang though, as neither franchise has ever advanced past the second round of the playoffs.
3) Atlanta Hawks (Bisons, Blackhawks)
Founded in 1937 as essentially a glorified recreation league for Goodyear, Firestone, and General Electric employees, the National Basketball League (NBL) quickly grew into a major player in American pro sports by the late '40s. At least 39 different franchises played in the NBL at one point, and five of them eventually reached the NBA after the NBL merged with the BAA in 1949. One of those teams was the Buffalo Bisons, a name and locale which lasted for about a month in 1946 before moving to Illinois and becoming the Tri-Cities Blackhawks. "Tri-Cities" is a term used to refer to the cities of Moline (where they played their home games), Rock Island, and Davenport, which sit along the Illinois/Iowa border. The Blackhawks was a nod to the Black Hawk War, which had been waged in the area in 1832 when the Sauk Tribe leader Black Hawk supposedly infringed on U.S. territory (it's most famous for being the first military experience of Abraham Lincoln). The Tri-Cities Blackhawks lasted for five years, during which they reached the NBL Western Conference Finals in 1948, losing to George Mikan's Lakers, and joined the NBA in 1949, under the tutelage of Red Auerbach in their initial season in the new league. By 1951 it was obvious the Tri-Cities area could no longer support a major pro sports team, and the Blackhawks relocated to Milwaukee, where they shortened the name to Hawks. In 1955 they moved again, to St. Louis, and in 1968 to their current nesting place in Atlanta.
4) Detroit Pistons (Zollner Pistons)
Around the same time the Bisons moved to Illinois and became the Blackhawks, a piston foundry owner named Fred Zollner founded his own NBL franchise in nearby Fort Wayne, Indiana, and named them the Fort Wayne Zeller Pistons, after his company. It seems almost like heresy today (imagine the Houston Lockheed Martin Rockets) but it was not an uncommon practice in the NBL, where teams had already been named after their owner's brand-name tires, clothing stores, car dealerships, and just plain company name. The Zollner Pistons were a dominant force in the NBL, with a commanding owner who led the charge to merge with the BAA in 1949 to form the NBA. With his fellow owners wanting to shed the amateurish industrial team past of the NBL, Zollner agreed to officially drop his name from the team (and abandon this logo featuring a truly terrifying robot with a "Z" on its chest), and thus it was the Fort Wayne Pistons joining the NBA. Even though they officially played as the Pistons, in and around Fort Wayne the team was still usually referred to colloquially as the Zollners until they moved to Detroit in 1957. Zollner spearheaded the move to the Motor City and ultimately owned the team until 1974. Even though the Zollner name no longer graces any NBA marquees, it does live on in the Western Conference championship trophy, which was renamed after Zollner in 1999, the same year he was posthumously inducted in the Hall of Fame.
5) Oklahoma City Thunder (SuperSonics)
When Clay Bennett moved his basketball franchise from Seattle to Oklahoma City in 2008, a name change was necessary for several reasons. Obviously, keeping the SuperSonics moniker not only made little sense in the new city (especially in an age where we all poke fun at the Utah Jazz and Los Angeles Lakers), but would be a slap in the face to Seattleites. Even more pressing was a lawsuit that Bennett lost, forcing him to leave the championship banners, retired jerseys, and other artifacts in Seattle. Though he officially still owned the SuperSonics name, Bennett wisely chose to leave that in Seattle as well, to avoid further litigation. Thunder beat out other fan-submitted suggestions like Bison, Energy, and Wind to become the team's new name, officially unveiled the month before the '08-'09 season started.
6) Philadelphia 76ers (Nationals)
The original BAA season in '46-'47 featured 11 teams, only three of which survived into the '50s. Seven other franchises were added in the meantime that folded almost immediately. The first decade of the NBA was a real feeling-out period, and it's no coincidence that the teams who survived were mostly the ones based in large cities. The era of regional teams was killed off by the early '50s, as franchises in Providence, Pittsburgh, Baltimore, Sheboygan, and Waterloo couldn't make it, while the franchises in Fort Wayne, Rochester, Milwaukee, and Minneapolis had to relocate to more heavily populated locales. As the league entered the '60s it was lean and mean, with teams in Boston, New York, Los Angeles, Philadelphia, Cincinnati (then a serious metropolis), Detroit, St. Louis, and Chicago. The one medium-sized city holdout was the Syracuse Nationals. That staying power in tiny Syracuse can be mainly attributed to the on-court success of the Nationals in the NBA's early years. Led by Dolph Schayes, considered the second greatest player of all-time after George Mikan at the time, the Nats reached the playoffs in all 14 years they played, winning the title in 1955 and playing in the 1950 and 1954 NBA Finals. They may have held out even longer, if not for the Philadelphia Warriors moving to San Francisco, leaving a huge East Coast city without a franchise. Syracuse became the Philadelphia 76ers in 1963, led by a new head coach in Schayes. 76ers, of course, is a nod to the Declaration of Independence, signed in Philadelphia in 1776. The name Nationals was a patriotic gesture by original owner Daniel Biasone, an Italian immigrant. It languished on the shelf for over 40 years before it was adopted again by Washington's new baseball team in 2005.
7) Los Angeles Clippers (Braves)
The first attempt at a major pro basketball team in Buffalo ended after a scant 13 games (see #3 above). Attempt number two was technically more successful, but that's obviously setting the bar pretty low. After fielding just eight teams for a number of years, the NBA responded to the impending encroachment of the ABA by expanding rapidly in the late '60s, including a franchise in Buffalo. The Braves' main home was the same as the Bisons' almost 25 years earlier, the Buffalo Memorial Auditorium, which was opened in 1940 and then renovated and expanded in 1970 to accommodate the Braves and a new NHL franchise, the Buffalo Sabres. But in their first few seasons they also played a handful of home games in nearby Toronto, as the NBA eyed a future relocation or expansion to Canada. The Braves floundered in the standings early, but rounded into a contender in the mid '70s thanks to the efforts of coach Jack Ramsay and star center Bob McAdoo. Despite the positive gains on the court, Buffalo quickly proved unable to support a basketball franchise. Owner Paul Snyder had a deal worked to sell and become the first NBA team in Florida, playing in the Miami area, but the city of Buffalo successfully sued to block the deal. It turned out to be all for naught, as Snyder was eventually able to unload the struggling franchise on John Brown, who used it as leverage to take over the team he really wanted. In an unprecedented move, he sought out Celtics owner Irv Levin, who was contemplating selling his franchise to try to start a new one in California (knowing that the NBA would never allow its cornerstone franchise to switch coasts). The two agreed to an even switch (brokered by David Stern), with Brown taking over the Celtics, and Levin inheriting the Braves, whom he almost immediately moved to San Diego, becoming the Clippers. The Clippers name was an ode to the city's maritime economy and history and stayed with the franchise six years later when they moved to Los Angeles.
8) San Antonio Spurs (Chaparrals, Gunslingers)
9) Brooklyn Nets (Americans)
10) Denver Nuggets (Larks, Rockets)
In essence a fly-by-night league on a shoe-string budget, it was not uncommon for the ABA to see regular city and name changes on the whims of its owners. Only two ABA franchises never changed names, the Indiana Pacers, who got called up to the NBA in 1976, and the Kentucky Colonels, who were forced to fold after being passed over in the merger. The three franchises that joined Indiana in the NBA from the ABA had all gone through at least one re-branding by that point. The San Antonio Spurs began life as the Dallas Chaparrals, one of the 11 original franchises for the inaugural '67-'68 ABA season. Attendance was spotty and in '70-'71 the team became the Texas Chaparrals, playing some games in Lubbock and Fort Worth. When that failed to bring in new fans, the team was sold to a consortium of San Antonio businessmen, who initially renamed the team the Gunslingers but eventually settled on the Spurs. Meanwhile, newly minted ABA owner Arthur Brown envisioned a patriotic New York team, so he named them simply the New York Americans and planned on home games at the 69th Regiment Armory in Manhattan. When the Knicks protested that encroachment, he was forced to instead relocate as the New Jersey Americans in Teaneck. They eventually made it back to New York in Long Island in 1968, renaming themselves the Nets to fall into a rhyming scheme with the NFL's Jets and MLB's Mets. As for Denver, they were originally called the Larks, after the Colorado state bird, but owner James Trindle had to sell the franchise before they ever took the court. New owner Bill Ringsby renamed them the Rockets, after a branded line of semis utilized by his trucking company. This stuck for seven seasons until 1974 when a merger with the NBA seemed imminent and the new Rockets were worried about having the same name as the existing franchise in Houston. Nuggets was chosen by fan vote, a reference to the area's gold rush history, and a nod to a Denver-based NBA franchise of the same name from the late '40s.
11) Sacramento Kings (Seagrams, Pros, Royals)
There hasn't been much tangible success in Kings franchise history, but few other teams can claim a timeline as rich and varied. They started life in upstate New York as the semi-pro Rochester Seagrams in 1923, sponsored by the local alcohol distillery. They changed it to the Pros in the early '40s to try and gain some credibility, and it seemed to work as they were invited to join the NBL in 1945. A name-the-team contest was held and the alliterative Rochester Royals was the winner. The name followed the franchise to Cincinnati in 1957, still appropriate in a place known as the "Queen City." In 1972 they moved again, this time to Kansas City, and due to the local baseball team already being named the Royals, they changed again, keeping things regal with Kings. The name remained in place when the team relocated to California in 1985.
12) Washington Wizards (Packers, Zephyrs, Bullets)
Opting to expand in 1961 with the league reaching unprecedented new heights of popularity, the NBA selected Chicago as a natural home for a new team. The Chicago Packers became technically the first NBA expansion franchise in '61-'62, with a name derived from the city's rich history of meat packing, especially at the Union Stock Yards, which were basically next door to the basketball arena. Despite the presence of Rookie of the Year Walt Bellamy, the Packers struggled to compete against more seasoned teams and ticket sales were flagging by season's end. Management fretted that sharing a name with a rival NFL team was one major source of the problem, so they changed it to the Zephyrs in '62-'63, as an ode to the Windy City nickname. But local interest was still lacking and in 1963 the franchise moved to Baltimore. They took on the new name of Bullets, as an ode to the Baltimore Bullets franchise that won the 1948 NBA title then folded in 1955 (the original Bullets derived the name from the historic Old Baltimore Shot Tower, a brick tower that produced shot in the 19th century and was once the nation's tallest structure). The Bullets moniker carried through the franchise's relocation to Washington in 1973, but was finally changed to Wizards by owner Abe Pollin in 1997, in response to the assassination of his good friend, Israeli prime minister Yitzkhak Rabin.
13) Los Angeles Lakers (Gems)
Most fans know that the Los Angeles Lakers began play in Minneapolis, and curiously kept the team name after moving from the "Land of 10,000 Lakes" to the land of 10,000 freeways. But it's a lesser-known fact that the Minneapolis Lakers came about as essentially a buy-out of a folded NBL franchise called the Detroit Gems. The Gems were owned by Maurice Winston, and derived their name from his Winston Jewelers company. They played their home games outside of the city at a high school gymnasium in Dearborn, drawing scant fans as they compiled one of the worst campaigns in pro basketball history. The Gems finished the '46-'47 NBL season with a record of 4-40, with all four victories coming at home. Two Minneapolis businessmen, who had been previously rebuffed from starting their own expansion NBL franchise, purchased the Gems for $15,000. They moved the team to Minneapolis, renamed them the Lakers, and inherited the Gems' top pick in the league's 1947 dispersal draft, which they used on George Mikan. After winning the NBL title in 1948, the Lakers then won five titles in their first six years in the NBA and played in one more NBA Finals in Minneapolis in 1959 before moving to Los Angeles.