Complex sentence: However, he was soon angrily aroused by the aggressive movements of the Federal government (President Abraham Lincoln's call for 75,000 volunteers to suppress the rebellion) and accepted a commission as a brigadier general in the Virginia Militia.
Split into simpler sentences: However, he was soon aroused by the actions of the Federal government when President Abraham Lincoln called for 75,000 volunteers to suppress the rebellion. He accepted a commission as a brigadier general in the Virginia Militia.