Answer: Europeans carried deadly (to the Native Americans) diseases
Explanation: When getting cured of a disease your body will have some type of immunity to the disease. If it is common from where you are then it wouldn't be too harmful. However, Native Americans getting new European diseases harmed them because this was new and they had no immunity. This made these diseases deadly to them.
N the first century CE, during the reign of Emperor Tiberius, silk had become a big problem. The luxury fabric, imported at great cost from China, had become a symbol of decadence and excess among Romans. In order to make their supply of silk last longer, merchants unraveled and re-wove their fabric into thinner, sheer garments. This practice had a side-effect of making the garments nearly transparent.
Seneca the Younger, a writer and imperial advisor, complained of people wearing silk:
"I can see clothes of silk, if materials that do not hide the body, nor even one's decency, can be called clothes. ... Wretched flocks of maids labor so that the adulteress may be visible through her thin dress, so that her husband has no more acquaintance than any outsider or foreigner with his wife's body.”
In the year 14 CE, the Roman historian Tacitus reported that the Imperial Senate made it illegal for men to wear silk, resolving that "Oriental [Eastern] silks should no longer degrade the male sex. "
This prohibition on silk did not last. The demand for silk continued to drive trade between the Roman Empire, China, India, and many places in between. To understand what caused this trade in silk, we need to look at how Chinese silk got to Rome.
