The colors blue and white are prominent in the flag and many symbols of Greece, as well as in the country’s architecture and cultural heritage. There is no definitive answer to why these specific colors were chosen, but there are several theories and historical explanations that provide some context:

Historical Symbolism: The colors blue and white have a long historical significance in Greece. They are believed to have been inspired by the blue sky and the waves of the Mediterranean Sea that surround the Greek islands and mainland. The white represents the purity and brightness of the Greek landscape under the Mediterranean sun.
Flag of the Greek War of Independence: During the Greek War of Independence against the Ottoman Empire (1821-1829), a blue and white flag was adopted as a symbol of the struggle for freedom. The nine horizontal stripes represent the nine syllables of the phrase «Ελευθερία ή Θάνατος» («Freedom or Death»), which became the motto of the revolution.
National Identity: Over time, the blue and white colors became strongly associated with Greek national identity, pride, and unity. As such, they were widely adopted in official state symbols, government buildings, and public spaces.
Influence of Neighboring Cultures: The colors blue and white have been used in the flags and symbols of various Mediterranean cultures, including the Byzantine Empire and the Venetian Republic, which had significant historical influence on Greece.
Cultural and Religious Significance: In Greek Orthodoxy, the color white is often associated with purity, while blue is connected to the Virgin Mary, who is an important figure in Greek religious and cultural traditions.

It’s important to note that while these are some of the reasons behind the prevalence of blue and white in Greek symbolism, the exact origins might be multifaceted and have evolved over time. The colors have become deeply ingrained in Greek culture and continue to be significant in various aspects of Greek life and heritage.