In 1954, Indonesia and China ratified a treaty stating that resident Chinese with dual nationality must choose one citizenship or the other by December 1962. The law required all Chinese Indonesians to choose between Chinese and Indonesian citizenship. Those who chose China return to China and those who chose to stay in Indonesia became Indonesia citizen.
Later, at Asia - Africa conference in Bandung 1955, Sukarno and Zhou Enlai signed a declaration stating that oversea Chinese as Indonesian citizen owed their primary loyalty to Indonesia not China/PRC. Indonesian Chinese have no connection with mainland anymore and they're not PRC responsibility.
Good move by your friend to finally assimilate BTW. There is no forcing to changing Chinese names today but having Indonesian name sure can help assimilation process better. A lot Chinese here today have dual names.
Indonesian Chinese are also free to preserve their culture and now open to pursue whatever career they want.
Respect.
Right now, Indonesian TVs are busy reporting Chinese New Year Celebration across the country.
So, Happy Chinese Year to Chinese everywhere.
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