Human Rights as a legal concept really took off at the end of the Second World War and the development of the Universal Declaration of Human Rights. Even before that, however, people have been discussing related concepts such as human dignity for centuries.
This guide focuses the 20th and 21st centuries but has some material related to development of contemporary concept of "human rights."
This page has a lot on it. You can use the following anchors (links down the page) to jump straight to a relevant box.