The coming of Islam in the district of Dairi started form Barus and developed by people from Aceh (some of them are clerics) who one of them is Koser Maha. Among of the developers of Islam in Dairi is still a mystery of their existence, such as Teuku Panjang Rambut (a Royal Man from Aceh with long hair) who was able to change his being or performance, and he is still alive as it is believed by the local people. Although the majority of the population of Dairi are non-Muslims , the teachings of Islam, however, can be received by the society because there is are similarities between the teachings of Islam and the culture of the Pakpak (the indiginous inhabitants of Dairi). The spread of Islam in Dairi was done through relation of kinship, ethical examples, mysticism, and olah kanuragan (martial arts) and kesaktian (magical power). These methods were very different from the way the Dutch colonial when spreading Christianity in Dairi that is done through the genocidal extermination or ethnic cleansing so that many Pakpak people were expelled from Dairi to some neighboring regions in order to save themselves. Luckily, even though the Muslims are minority in Dairi, but social relation in terms of religious harmony is very good.