When did drinking coffee became popular in the Middle East? Europe? Was coffee known before for other attributes (medicine, ritual, etc..) before it was a popular drink? At what point did coffee spread as a popular drink and what are the factors that helped it become widespread?
References to primary sources is greatly appreciated, thank you in advance!
Coffee appeared in Europe around the late 16th century and early 17th century. Of course, like many liquids, there were all kinds of opinions about its purported health benefits.
However, the main benefit was the fact that it lead to a decline in the consumption of alcohol. Alcohol had previously been the best way to consume uncontaminated water, so it was common for much of the population of Europe to be mildly intoxicated for much of the day. Coffee offered a better way to consume uncontaminated water without getting drunk, and the mild amount of caffeine was purported to encourage clear thinking.
Coffee was hailed as part of the age of rationalism. Coffee shops became centers of intellectual engagement as part of an increase in interest in philosophy and sciences more generally in Western Europe. While coffee was later surpassed by tea in popularity in the UK, it continued to be popular in continental Europe.
One of the better written sources on the subject is http://www.amazon.com/A-History-World-6-Glasses/dp/0802715524