This question relates to a hypothesis my wife is researching, and together we are finding information and sources difficult to aquire. Specifically, she is interested in how attitudes may have changed, for better or worse, after the rise of trade regarding these commodities.
Why these specific commodities, if you don't mind me asking?
Hello there. Your question seems to be related to school work, so we just want to remind you, and any potential respondents, that our rules DO permit people to ask for help with their homework, so long as they are seeking clarification or resources, rather than the answer itself. This policy is further explained in this META Thread.
Additionally, while our users may be able to help you out here, we hope that you also will take the time to check out our six-part series, "Finding and Understanding Sources", which should hopefully prove to be helpful for your wife as she continues in her research.