Indonesia is a key case for evangelical politics in Asia, and merits a deeper study than is given here. One of the most populous countries in the world, it is also significant in evangelical terms by Asian standards. Its place on the fringe of Islamic expansion (which, as Walls (1996) says, is ‘progressive’, spreading out from a constant heartland, unlike Christianity's ‘serial’ expansion involving jumps from one heartland to another) makes it a ‘swing’ case for the politics of Islam, and consequently of Asian Christianity as well.

Indonesia has similarities with Malaysia, but also striking differences. Once again, there is Christianity amongst the Chinese (fewer than in Malaysia) and small ethnic groups of animist background. There are some small-scale Christian societies, such as the totally Christian island of Kisar, evangelised by Indonesian missionaries since the 1920s. Irian Jaya is 60 per cent Protestant – a stark contrast with Bali's 0.5 per cent and Java's 2.5 per cent. Johnstone (1993) gives 9.3 per cent Protestant for the whole country, but Hefner estimates 6 per cent. As Hefner remarks, about 4 per cent of ethnic Javanese are now Christians. He cites a missionary author to the effect that this represents ‘the largest group [in modern times] ever to become Christians of a Muslim background’ (1993: 100).