Okay kiddo, let's start with what "Mariology" means. Mariology is the study of Mary, the mother of Jesus.
The Roman Catholic Church has a very special place for Mary, and this has been the case for a long time. In fact, the belief in Mary's importance goes all the way back to the early Christian Church, but it really grew in popularity during the medieval times.
One of the most important beliefs about Mary is that she was a virgin when Jesus was born. This is called the "Immaculate Conception." The Roman Catholic Church teaches that Mary was both born without sin herself, and that she was specially chosen by God to be the mother of Jesus.
Another important thing that the Church believes about Mary is that she was assumed into heaven after her earthly life was over. This means that she did not experience death like regular people do, but was taken up into heaven body and soul.
The Church has many different celebrations and practices that honor Mary. For example, the month of May is dedicated to her, and many people create special altars and devotions in their homes during this month.
Overall, the history of Roman Catholic Mariology is the story of a belief that Mary is a very special and important figure in the Church, and that she has a special place in the hearts of Catholics all over the world.