on January 1, 2011, President Ma entitled his New Year's address "Building up Taiwan, Invigorating Chinese Heritage", which stressed "Chinese culture and virtues, such as benevolence, righteousness, filial devotion, respect for teachers, kindness, and simplicity". Thailand Vietnam Hoa people, or ethnic Chinese in Vietnam, form a significant minority in the country with a presence traced from the Nanyue era and became organized since the foundation of Later Lê dynasty. Chinese immigration to Vietnam peaked during the late 19th to mid-20th century, when China experienced political turmoil and life quality stagnation, as well the communist takeover in 1949 and business incentives provided by the French colonial government. The Hoa largely integrated well, forming a large portion of the Vietnam's middle and upper class and playing an important role in its economy. In addition to their native dialects and/or Cantonese (the lingua franca of Chinese in Southeast Asia), Vietnamese proficiency rates among the Hoa were extremely high and were the largest among Vietnam's ethnic minority groups. Most Hoa eventually considered themselves as Vietnamese first and then Chinese, with those with origins not from mainland China identifying themselves to their specific place, such as "Hong Kong Chinese" or "Macau Chinese", especially in South Vietnam. Following the Fall of Saigon and communist reunification of the Vietnam, most Hoa in the former South Vietnam opted to immigrate to other countries, especially the United States, France and Australia, rather than communist-controlled China. Only ethnic Chinese persecuted by government in northern Vietnam chose to immigrate back to China, especially to Guangxi Province. Overseas Chinese with origins from Vietnam usually interact with both local Chinese and Vietnamese communities. However, the presence of non-Cantonese speaking and/or mainland Chinese-descented communities results in the community identifying itself with the Vietnamese community instead, as in the case with the Chinese community in France. North Korea Using Hanja (한자,漢字), or Chinese characters in Korean language, was banned in 1949 in North Korea by Kim Il-sung. Kim banned the use of hanja because he viewed the abolishment of hanja as a symbol of decolonization and Korean nationalism. South Korea Hangul was made the official script of the Korean language since 1948, replacing Hanja, and Hanja is not required to be learned until high school as an elective course in South Korea. Former Mayor of Seoul Lee Myung-bak's move to change Seoul's official Chinese name from Hancheng (한성,漢城) to Seoul (서울) in 2005 as a