China influenced Vietnam's culture in many ways even before the French conquered Vietnam. Nationalism in Indo-China developed in a colonial environment. Indo-china comprises the modern countries of Vietnam, Laos and Cambodia. Its early history shows many different groups of people living in this area under the shadow of powerful empire of China. Though Vietnam gained formal independence in 1945, before India, it took 3 decades to attain republic. Even when an independent country was established in what is now northern and central Vietnam, its rulers kept on maintaining the Chinese system of government as well as Chinese culture. In Vietnamese, Chinese was the language of elite. Confucianism, the religion of china, was followed by Vietnamese. Vietnam was well linked to the maritime silk route. The maritime silk route made an important contribution in exchange of goods, people and ideas. The French found it difficult to dislodge the influence of Chinese culture on Vietnamese.