I believe you are refering to the Caravan raids which were done by people of the islamic faith.
In total there were 11 total raids
the purpose of these raids was to plunder these people of all there riches
they were believed to have been told by Allah(the higher power of the Islamic faith) to go forth and plunder these people of there riches
They were miltiray orders were established in the early 12th century
Arid and semi-arid regions often have to go through long periods of drought.A drought is basically a situation in which an area of land gets insufficient rainfall, causing a lot of suffering to those who inhabit these regions. Some of these drought-prone areas include deserts of Australia, parts of India and Sudan among others.
The answer is reform movement. It is a type of social movement that targets to make continuing change, or change in certain parts of society, rather than rapid or fundamental changes. A reform movement is notable from more radical social movements such as revolutionary movements. Reformists' thoughts are often deal with in liberalism, although they may be embedded in socialist or religious concepts. Some depend on on personal transformation; others count on on small collectives, such as Mahatma Gandhi's spinning wheel and the self-sustaining village economy, as a mode of societal change. Examples of reform movements are labor movement, animal rights movements, anti-nuclear movement, Mothers against Drunk Driving, and the disability rights movement.
Nazi Germany and the Soviet Union