Recalling a bit of my classes at High School (Universal History and Art History), the pagoda refers to a mainly funerary monument, where the Eastern religious community is dedicated to Buddhist cult. Like tombs or places of cult, they are located near the temples, and tend to attract pilgrims who wish to worship the remains of important Buddhist monks.
Some experts point out that the Pagoda comes from the Stupa of India (a tumulus (mound) in the shape of a hemisphere, which was already given in ancient religions and that was accepted by Buddhism to keep in it the relics of the Buddha, ashes of some saint, ritual objects, cult images considered miraculous ...). A photo of what a stupa is can be seen at the following link: http://www.yuanfangmagazine.com/artes/origen-la-pagoda/
The evolution of the stupa is the pagoda, more widespread in China or Japan and also Vietnam. Although there were already stupas of square base with superior bodies that symbolized the five elements - earth, water, fire, air and sky - it will be in the pagoda where these five symbolic planes will appear most obviously. This is how the pagoda is a representation of the Universe. The square or octagonal base on which it sits symbolizes the earth; the central pillar that ascends from the base to the highest point, the axis of the world. Greetings @nameless-berk