Many people who are religious or identify with a certain religion should be familiar with the history of their religion. However, some people do not have anything to do with religion, but it is still important for them to be familiar with church history. The reason is that it is history.
Church history was still a part of history and people need to know about history. They should learn about the people and events that shaped the world. When people learn about the history, they may be more accepting of the people who follow that religion. Acceptance and tolerance are needed today with everyone. When people become more knowledgeable about religions, they will understand and accept why people practice that religion.