First of all. A definition of these and other terms is necessary:
- Dar Al Islam: in Arabic it literally means the "House of Islam". It is an Islamic political/legal term referring to the countries where Islam is practiced by the vast majority of the inhabitants and where the government and all rulers are are Islamic.
- Dar Al Harb: literally means the "house of war" and applies to all countries that do not have an armistice or a treaty of peace with Muslims. According to Islamic jurisprudence, it is not only licit and legal to attack and harass such countries by any means possible until they accept to convert to Islam or accept being the vassals of an adjacent Caliphate.
- Zanj: Arabic meaning "black" or "<u>negro</u>" was the region of Southeast Africa on the Swahili coast that was populated by black Africans. Zanj was the name that Medieval Muslim geographers used to refer to that area. Arab and Persian colonists founded settlements on the coastal areas of these regions. They ruled them according to Sharia Law and held all political and economic power. The blacks or Zanj were either conscripted to fight in Muslim armies or were sold as slaves to all the Islamic countries located on the coasts of the Indian Ocean.
Now that those definitions have been provided the answer is much simpler:
In Dar Al Islam, the Muhammadans were the majority and they were above all other social groups. Society was organized around Islam and the government and the religion were one since Islam does not recognize the separation of religion and state. It is the "abode of peace" since it is considered Islamic land and all Muslim subjects enjoy supremacy and several rights and privileges over non-Muslim majorities. Any of the Muslim Caliphates is considered to be Dar Al Islam.
Zanj on the other hand, is located within what Islamic lawmakers considered Dar Al Harb, the "house of war". The inhabitants of this area were animist, black unbelievers that according to Islamic religious and political doctrine were legally under the power of Muslims that could rule them and enslave them and use them as cannon fodder for their armies. Of course, the Islamic settlements where the Arab and Persian rulers lived were small Dar Al Islam enclaves since the rulers and the laws were Islamic but Muslims were not the majority and Islam was officially at war with the local Zanj unbelievers. Furthermore, the Zanj were not Arabs and spoke no Arabic so they were of course barred from any government position and were not even protected as <em>dhimmis </em>since they were not a People of the Book. Therefore in Zanj, the relationship between government and religion was a colonial one, unlike the one in Dar Al Islam.
