Greece A1

The first official regional club basketball tournament in Greece, took place in the year 1924. While the first edition of the Greek basketball championship took place in the 1927–28 season, the first fully organized Greek basketball championship began. The league was originally organized by the Hellenic Amateur Athletic Association (SEGAS). There have been four different official championship eras. The first era was the Panhellenic Championship (Πανελλήνιο Πρωτάθλημα), which lasted from the 1927–28 to 1962–63 seasons, when the champions of every regional district played each other to decide the Greek Champion. The second era started in the 1963–64 season, when the A National Category (Α' Εθνική Κατηγορία), or Alpha National Category was founded.

In 1969, the Hellenic Basketball Federation (E.O.K.) took over the duties of overseeing the competition, and did so until the year 1992. The third era of the championship existed between the 1986–87 and 1991–92 seasons, when the first division A1 National Category (Α1 Εθνική Κατηγορία), with a regular season and playoffs, and the second division A2 National Category (Α2 Εθνική Κατηγορία) were formed. The 1988–89 season, marked the first time that Greek Basket League teams were allowed to have foreign players on their rosters.

The fourth era of the championship began in the 1992–93 season, when the Hellenic Basketball Association (HEBA) took over the competition and renamed the first division the HEBA A1 (ΕΣΑΚΕ Α1). The league was then renamed to Greek Basket League (Ελληνική Μπάσκετ Λιγκ), starting with the 2010–11 season.

The Greek League has been one of the most competitive basketball leagues in Europe through the years, and it was widely regarded as the second best national domestic league in the world, after only the NBA, in the 1990s decade. It currently ranks among the best national domestic leagues in the world (excluding the NBA), such as Liga ACB in Spain, VTB United League (counts as the domestic league for Russian clubs), and BSL in Turkey. Historically, the league has been ranked as one of the top 3 European national domestic leagues, along with Italy's Lega Basket Serie A and Spain's Liga ACB, under the historical European national basketball league rankings and European national basketball league rankings.

The league has several European historical basketball powers, which also belong to some of the most traditional European basketball clubs, especially Panathinaikos, Olympiacos, and AEK (which had great success in the 1960s), which are three of the most successful European basketball clubs of all time. Also, Aris, led by Nikos Galis, Panagiotis Giannakis, and Slobodan "Lefteris" Subotić, was the dominant Greek club, and one of the most powerful European teams in the 1980s. Other clubs that have had significant success throughout the history of Greek basketball, as well as success in European basketball, are PAOK and Panellinios. The first five aforementioned clubs (Panathinaikos, Olympiacos, AEK, Aris and PAOK), are also the most widely supported by fans in Greece.

Despite the championship having been contested 84 times, only nine different clubs have won it so far. The dominating club has usually been Panathinaikos, having claimed the championship 40 times. Since the foundation of the Alpha National Category in the 1963–64 season, only two teams have participated in every season of the competition, Panathinaikos and Aris.