Chi. Chikyuu No Undou Ni Tsuite is a Manga/Manhwa/Manhua in english language, Seinen series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.nl fastest updating comic site. The Summary is

The setting is 15th century Poland. It was a time when heretical ideas lead those to who possessed such a mindset to being burned at the stake for their beliefs.
The protagonist, Rafal, a child prodigy, is expected to major in theology, the most important subject at the time, at the university.
One day, however, he comes across a mysterious man, and is now studying a possible "truth" in the midst of heretical thought!