Orphans of the Sky by Robert A. Heinlein

⭐️⭐️⭐️ Nice, quick read. As far as I understand, it's one of the foundational Generation Ship stories. First published as 2 short stories in the 1940s, it was published as a novel in 1963. 

I found myself quite immersed in the world of the book. A world where people have forgotten where they came from and where they are going. Society has decayed and become stratified into upper and lower classes. Although the novel depicts events in the future, I often had the impression that I was reading about 19th-century people. At times, I found myself imagining the generation ship as an old fashioned pirate ship. The problem with this was I had to make an effort to believe they were travelling in deep space. 

Anyways, I recommend this novel as a window into how the concept of generation ships has developed and changed over the decades.