Most of the differences are regarding Sharia laws devised through Ijtihad where there is no such ruling in the Quran or the Hadiths of Islamic prophet Muhammad regarding a similar case. As these jurists went to new areas, they were pragmatic and continued to use the same ruling as was given in that area during pre-Islamic times, if the population felt comfortable with it, it was just and they used Ijtihad to deduce that it did not conflict with the Quran or the Hadith. As explained in the Muwatta by Malik ibn Anas. This made it easier for the different communities to integrate into the Islamic State and assisted in the quick expansion of the Islamic State.