This paper looks into the historic development of political Islam in Bangladesh, the third largest Muslim country of the world. Identifying origins and sociology of Bengali Muslims, this paper finds that development of political Islam took place in Bangladesh mainly in four phases: the Turkish war and the founding of the Khilafat movement during the First World War; the Oil crisis in the 1970s and the boost of Islamic institutions and practices in Bangladesh's political discourse, mainly supported by the Middle Eastern countries; the Soviet-Afghanistan war and its linkage with Bangladeshi radicals in the 1990s; and by the globalization of war between Al-Qayeda and West and its implication on Bangladesh through the rise of extreme groups.