Despite being one of the most significant developments in Indonesian history, historical evidence is fragmentary and generally uninformative such that understandings of the coming of Islam to Indonesia are limited; there is considerable debate amongst scholars about what conclusions can be drawn about the conversion of Indonesian peoples.[1]:3 The primary evidence, at least of the earlier stages of the process, are gravestones and a few travellers' accounts, but these can only show that indigenous Muslims were in a certain place at a certain time. This evidence cannot explain more complicated matters such as how lifestyles were affected by the new religion or how deeply it affected societies. It cannot be assumed, for example, that because a ruler was known to be a Muslim, that the process of Islamisation of that area was complete; rather the process was, and remains to this day, continuous in Indonesia.