<span>Sep 18, 2013 - India, Bangladesh, and Pakistan are the top countries of origin of temporary labormigrants in the United Arab Emirates. ... Over the past few decades, the United Arab Emirates (UAE)—one of the world's pre-eminent oil-rich nations located in the Gulf Cooperation Council (GCC) region ...</span><span>
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Depends on the context. If you told more then I could help.
It was caused by a mix of different scenarios. Rome was constantly attacked by Barbarian tribes; they were over-expanded, which made it really hard for them to keep their entire empire under control; they had a lot of economic problems and relied too much on slave labor; and they spent way too much money on their military, just to name a few factors.