Which factor contributed to the spread of the black plague?

Europe during the Black Plague had very poor sanitary conditions. Avoiding the infection was near impossible due to the poor living conditions and no knowledge of how to prevent the plague

Explanation:

Crusades

Explanation:

one of the main reasons was definitely slavery. back in 1861, republican abraham lincoln was elected and ended up being a major influence in the slavery business. slavery greatly affected the texas economy because back in 1845 during the annexation of texas, slaves became a big part of the texas population. many texans that were in favor of the secession influenced groups through party ties.