Alexander was imprisoned for making a sarcastic comment on the militaries lack of preparation and competence in a personal letter to a friend. He studied math, philosophy history and literature. He was well educated there was made a commander and received recognition for heroism on multiple occasions. He was sentenced to 8 years in a labor camp for criticism of Stalin.
He wrote A day in the life of Ivan Denisovich, and The Gulag Archipelago and other books. Today in Russia his 2000 page Gulag Archipelago is required reading.