The statement that comes in between is:
Anderson became the commander of Fort Sumter.
Step-by-step explanation:
The puzzle talks about one of the first battles in the lead up to the Civil war in the US.
This was the siege of and the eventual surrender of the Fort Sumter, a fort from the colonial time that was held by a militia form the south after making the union army surrender.
This was the first major incident in the war.
Anderson was one of the veteran generals who took over the fort from the US army after opening fire on it and this was the incident that kicked off the civil war.