The Lunar Mansions have their origins in Mesopotamia but were developed fully in India from where they were incorporated into the Persian and Chinese astrological traditions.

Lunar Mansions are also referred to as Lunar Stations or Lodges. In India they are known as the Nakshatras (literally meaning "asterism" or "the deity figure of the stars"); in Arabic, they are called Manazils or Manzils (meaning "house or abode"); and in Chinese, Hsiu or Sieu, Xiu (meaning "lodge"). 

As a calendrical system, Lunar Mansions divide the sky into 27 or 28 sectors, each marked by key fixed stars or asterisms along the path of the Moon. There are conflicting modern calculations of the Mansions. For example, Astro-Seek's calculator for determing the tropical boundaries of the Mansions don't line up with the actual asterisms. I have found that the position of the fixed stars is of utmost importance as they are the basis and the guiding compass for identifying which Mansion the Moon (or any other planet) is passing thru. It is the asterisms and the star deities that give the Mansions their significance. Keep this in mind when tracking the Moon’s transits.