According to the Islamic theory of landed property, development and fructification of what one possesses binds ownership. Property can be acquired through developing and utilizing arable fertile (farming) land with no previous claim of ownership.* However, the right someone has acquired to a piece of land is not lost merely through non-use; it vanishes only if someone else brings that land under cultivation.* The purpose of such law is to benefit the general public by bringing life to the virgin land and to ensure the continuity of utilization. * No privately owned natural resource is to be left unused. Meanwhile, the concept of sharecropping is acknowledged by most Islamic schools of thought as a justifiable mode of acquiring property rights.

A couple of other interesting discussions about different types of property rights in that article too. Critical to keep in mind that it’s a religion and that there are multiple traditions/legal schools of thought. (Shia versus Sunni is the biggest rift, but there are others.)

Fear of Islamic socialism was why the US kept the Shah in power.

As far land borders - that is seriously a huge and complicated and difficult topic. (Numismatic research - coins - often shows how often we don’t really have documentation of what was happening. Kingdoms that are only known to exist because they put out a few pieces…) That’s the kind of topic that people do post doc work on.