Who is Joshua Lawrence Chamberlain from Gods and Generals and what is their importance?

Joshua Lawrence Chamberlain did not have any military experience before the war. He was an academic.

When Chamberlain volunteered to fight for the Union, he joined an inexperienced regiment. They had no uniforms or weapons; they had no sense of order. Drilling and training was extensive, and officers had to learn how to lead.

Fredericksburg was Chamberlain's first experience in combat. It was also his first experience as commander of the regiment when his commanding officer was called away. This experience led him to question all of his passionate reasons for fighting, and he found that none of his initial reasons gave him an emotional bump when bullets were flying around his head.