So my current big question is that there was a theoretical golden age in the islamic world of science and study (especially astronomy), and that it ended somehow. So how did it end and why?
And if they where so much more scientifically developed then the west, then why did they not kick its ass more then they did? What did the golden age entail in practice? Bigger Buildings? Better metals? Better medicine?
To answer the second part first, they probably kicked ass more than you think. Western history classes tend to skip over just how much Islam kicked ass. It's more easily summarized with a map of the expansion of Islam:
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That said, conquest wasn't actually a focus of the Golden Age, and a lot of the key expansions were before the Golden Age. Personally, I know of the Golden Age primarily from the history of science and mathematics. Key points: you're using Arabic numerals in your math, and our whole system of math notation is based on algebra - which comes from the title of al-Khwarizmi's 833 book on the subject. One simple metric is how well different scholars calculated the value of pi. Around the medieval era, the record-breaking calculations were:
In 150, Ptolemy in Egypt calculated pi to 3 decimal places (as 377/120).
In 480, Zu Chongzhi in China calculated pi to 7 decimal places.
In 1400, Madhava of Sangamagrama in India calculated pi to 10 places.
In 1424, Jamshid al-Kashi in Persia calculated pi to 16 decimal places.
The Golden Age included a lot more than just science and math, though - with influential works in poetry, philosophy, drama, and more.
I hear some explanations of how the Mongols screwed everything up, but the mongols screwed things up for allot of people, and Im not certain how much the mongols actually destroyed because I know they accepted knowledge from places they conquered to some extent.
Im no historian, but I just felt like asking these questions somewhere and was hoping to get some pointers where I could get some answers.
The reasons and exact time of the decline of the Islamic Golden Age are subject to a lot of debate. I'd say it undoubtedly came down to a number of factors. The Mongols were one, for certain. They did leave a lot of lasting change, which is often brushed over in history.
There are economic and cultural shifts that ended with the Golden Age, but it's unclear which of them are symptoms and which are causes. There did grow to be a more dominant ruling class, and more restrictive laws on expression in favor of strict rule by political and religious authorities.
One that you might not have heard of is the environmental factor. The lands of Arabia and Persia are now known primarily as deserts, but in early times, Persia was known as the Fertile Crescent. Some combination of farming and other environmental factors, though, were slowly causing the deserts to expand.
Also, it's not a direct cause -- but one thing that truly left the Islamic world behind was the Age of Sail and the New World. The Islamic traders had always been poor sailors, and were mostly based around land routes. So they were outpaced and left behind by the Europeans, especially after the New World was conquered. Resources from the Americas radically changed Europe, giving them resources that put them ahead of the Ottomans and China. Without the resources from the New World, Europe's advance might not have been as pronounced.