The correct answer is: political instability, military conflict, and economic crisis.
Political instability: at the end of the 4th century AD, the Roman empire was going through a political crisis. While the emperor Theodosius tried to handle the social uprisings between Christians and non-Christians, he was struggling against the usurper Magnus Maximus and the empire was facing cases of corruption in the political sphere that diverted public funds from the military needs. Due to these reasons and for administrative purposes, Theodosius decided to establish Christianity as the official religion of the empire and divided the empire into two parts: the Western Roman Empire, with its capital in Ravenna, and the Eastern Roman Empire, with its capital in Constantinople.
Military conflict: while the Roman Empire was facing these internal problems that weakened it, there were urgent problems in its borders since many barbarian invaders were attacking Roman positions from the outside. The Huns from the East, led by Attila, devastated a great portion of the empire, Saxons invaded Britain, Goths and Lombard people from the North as well invaded Italy and Hispania. The Roman army for the first time was not in the position of facing so many fronts at the same time.
Economic crisis: the enormous Roman administrative device was going through a financial crisis. It was so big that it did not find the necessary resources to satisfy its needs. Gold mines that used to fuel the economy were very far away, difficult to achieve, and the Empire had to make a large number of official coins out of copper provoking a great devaluation of the Roman currency.
He created a trust that controlled 90% of the nation's oil refineries. If I remember correctly, horizontal integration is when you buy out the other businesses in the same market, while vertical integration is where you take control of everything related to your product, which is getting the oil, refining it, and distributing it, rather than selling those tasks out to third parties.
The South was speaking to Britain and France and was asking for military aid against the North and basically they said "Hey win a strategic battle on Northern land and we will help you." Well after the South didnt win the battle because in all terms the Battle of Antietam was more a draw then a loss for either side but because it wasnt an outright victory both the British and French retracted their offer of aid.
