Azzurro (literally, azure) is the national color of Italy. The light blue color, together with the tricolor flag, is a symbol of Italy.
The origins of the color date back to 1366, when Conte Verde, Amedeo VI of Savoy, displayed a large blue flag in tribute to the Madonna on his flagship, next to the banner of Savoy, while on a crusade organized by Pope Urbano V. He used that opportunity to proclaim "azzurro" as the national color.
From that time forward, military officers wore a blue-knotted sash or scarf. In 1572, such use was made mandatory for all officers by Duke Emanuele Filiberto of Savoy. Through several changes over the centuries, it became the chief insignia of rank. The blue sash is still worn by officers of the Italian armed forces during ceremonies. The Italian presidential banner is bordered in azzurro, too (in heraldry, the color signifies law and command).
Also in tribute to religious figures, the ribbon of the Supreme Order of the Santissima Annunziata, the highest Italian chivalric ensign (and among the oldest in Europe) was light blue, and blue ribbons are used in the military for certain medals (such as the Medaglia d'Oro al Valor Militare and Croce di Guerra al Valor Militare).
During the twentieth century, azzurro was adopted as the official color of athletic jerseys for national Italian teams. The Italian national soccer team, as a tribute to the Royal House of Italy, wore blue shirts for the first time in January 1911, and the maglietta azzurra quickly become the symbol of the sport.
The color took several years to establish itself as part of the uniform for other national teams. In fact, during the 1912 Olympic Games, the most popular color remained white and persisted, even though the Comitato Olimpico Nazionale Italiano recommended the new jersey. Only during the 1932 Olympic Games in Los Angeles did all Italian athletes wear blue.
The national football team also briefly wore black shirts as demanded by Benito Mussolini. This shirt was used in a friendly game with Yugoslavia in May 1938 and during the first two World Cup matches that year against Norway and France. After the war, even though the monarchy was ousted in Italy and the Italian Republic was born, blue uniforms were kept for national sports (but the royal crest of Savoia was eliminated).
It's worth noting that the color also frequently serves as the nickname for national Italian sports teams. Gli Azzurri refers to the Italian national soccer, rugby, and ice hockey teams, and the Italian ski team as a whole is referred to as the Valanga Azzurra (Blue Avalanche). The female form, Le Azzurre, is likewise used to refer to Italian women's national teams.
The only Italian sports team that doesn't use a blue shirt for its national team (with some exceptions) is cycling. Ironically, there is an Azzurri d'Italia award in the Giro d'Italia in which points are awarded for the top three stage finishers. It's similar to the standard points classification for which the leader and final winner are awarded the red jersey but no jersey is awarded for this classification-only a cash prize to the overall winner.