Complex sentence: In the Civil War, he was first a colonel of the 27th Illinois Infantry and then a brigadier general, took part in the sieges of Corinth and Vicksburg, and in 1865 was brevetted major general of volunteers while commanding the District of Eastern Arkansas.
Split into simpler sentences: In the Civil War, he was first a colonel of the 27th Illinois Infantry and then a brigadier general. He took part in the sieges of Corinth and Vicksburg, and in 1865 was brevetted major general of volunteers while commanding the District of Eastern Arkansas.