The Greco-Turkish War is declared between Greece and the Ottoman Empire.

The Greco-Turkish War of 1897 or the Ottoman-Greek War of 1897, also called the Thirty Days' War and known in Greece as the Black '97 or the Unfortunate War, was a war fought between the Kingdom of Greece and the Ottoman Empire. Its immediate cause involved the status of the Ottoman province of Crete, whose Greek-majority population had long desired union with Greece. Despite the Ottoman victory on the field, an autonomous Cretan State under Ottoman suzerainty was established the following year, with Prince George of Greece and Denmark as its first High Commissioner.

The Ottoman Empire, also called the Turkish Empire, was an imperial realm that controlled much of Southeast Europe, West Asia, and North Africa from the 14th to early 20th centuries; it also controlled parts of southeastern Central Europe, between the early 16th and early 18th centuries.