Surabaya (formerly Soerabaja, Soerabaia or Surabaja) is Indonesia's second-largest city with a population of over 3.1 million (5.6 million in the metropolitan area), and the capital of the province of East Java. It is located on the northern shore of eastern Java at the mouth of the Mas River and along the edge of the Madura Strait.
To some Indonesians, it is known as "the city of heroes" due to the importance of the Battle of Surabaya in galvanizing Indonesian and international support for Indonesian independence during the Indonesian National Revolution. Surabaya is also known as the birthplace of Indonesia's first president, Sukarno.
The earliest record of Surabaya was in a 1225 book written by Zhao Rugua, in which it was called Jung-ya-lu, the ancient name of Surabaya. Ma Huan documented the early fifteenth-century visit of Zheng He's treasure ships in his 1433 book Yingyai Shenglan: "after traveling south for more than twenty li, the ship reached Sulumayi, whose foreign name is Surabaya. At the estuary, the outflowing water is fresh".
In the fifteenth and sixteenth centuries, Surabaya was a sultanate and a major political and military power in eastern Java. It entered a conflict with, and was later captured by, the more powerful Sultanate of Mataram in 1625 under Sultan Agung. It was one of Mataram's fiercest campaigns, in which they had to conquer Surabaya's allies, Sukadana and Madura, and to lay siege to the city before capturing it. With this conquest, Mataram then controlled almost the whole of Java, with the exception of the Sultanate of Banten and the Dutch settlement of Batavia.
The expanding East Indies Companies took the city over from a weakened Mataram in November 1743. Surabaya became a major trading center under the Dutch colonial government, and hosted the largest naval base in the colony. Surabaya was also the largest city in the colony serving as the center of Java's plantation economy, industry and were supported by its natural harbor. In 1917, a revolt occurred among the soldiers and sailors of Surabaya, led by the Indies Social Democratic Association. The revolt was firmly crushed and the insurgents given harsh sentences.
Japan occupied the city in 1942, as part of the occupation of Indonesia, and it was bombed by the Allies in 1944. After that it was seized by Indonesian nationalists. However, the young nation was soon put into conflict with the British, who were caretakers of the Dutch colony after the surrender of the Japanese.
The Battle of Surabaya, one of the most important battles of the Indonesian revolution, started after the killing of the British Brigadier Mallaby on October 30, 1945 near Jembatan Merah (the "Red Bridge"), allegedly by a stray bullet. The Allies gave an ultimatum to the republicans inside the city to surrender, but they refused. The ensuing battle, which cost thousands of lives, took place on November 10, which Indonesians subsequently celebrate as Heroes' Day (Hari Pahlawan). The incident of the red-white flag (the Dutch national red-white-and-blue flag at the top of Yamato Hotel's tower that was torn into the Indonesian red-white flag) by Bung Tomo is also recorded as a heroic feat during the struggle of this city.