Why were they spilt even thought there on the same content?
(The union and the confederate flag)

The scholars immediately disagreed over the causes of the war and disagreement persists today. Many maintain that the primary cause of the war was the Southern states' desire to preserve the institution of slavery. Others minimize slavery and point to other factors, such as taxation or the principle of States' Rights.

The Confederates had their own flag because they had different beliefs than the Union.

Explanation:

The Confederates wanted more freedom and the ability to have slaves, and the Union didn't, so they seceded from the Union. This succession gave them the opportunity to create a new flag, as the Union already had one (what is now referred to as the American flag). The Confederacy kept the same basic principles, but changed the flag to one that better reflected them.

the roman army grew in size and became dominant in the mediterranean region.

i do not have access to the graph, but from 2001 to 2011 the rate of unemployment in the united states changed drastically. it remained relatively steady, at 5 percent, on average (4.4 percent in 2006 due to the economic expansion and 6 percent in 2002 as a result of the elevated costs of the war of terror) until 2008. it was then when the financial crisis, the worst since the great depression of 1929, occurred. during the recession that followed, the unemployment rate reached almost 10 percent in 2009, and in 2010 it was above 9 percent. by 2011 job losses had been continuous and prolonged for months, but the rate decreased timidly.