This article talks about the dynamic of the formation of Semarang cultural identity especially Semarang arts and Semarang ritual tradition. Semarang is a city which has an unique growth and character. Based on traditional historical resources, Semarang had been already existed since the period of the expansion of Hindu culture. Its early development as a city ran parallel with the islamization in this region. Semarang was formed administratively on May 2 - 1547, when Ki Pandanarang II was chosen as the regent of this city by the Sultan of Pajang kingdom, Hadiwijaya. The administrative development of Semarang could not be separated from its good economic and geographical position. Because of its strategic position, the Dutch came to occupy this region and also spread its political, economic, social, and cultural influences in this region. To face these influences of foreign cultures, the people of Semarang took the way of peace and hybrid, so it could be argued that Semarang become a good medium of hybrid culture. This could also be concluded that Semarang is a maritime city which can be viewed as a good medium for strengthening Indonesian national identity: unity in diversity.