Masakazu Natsuda was born in Tokyo in 1968 and studied there and in Paris. He says that this 1996 composition was his "most Oriental piece" to that date. While it is actually composed according to Western structures and techniques (especially the use of modes and layers of complex rhythms), the resulting sound is very reminiscent of Korean music in particular.
Its treatment of time is particularly Asian. In contrast to the Western linear view of time, the concept of time used here is circular (or spiral), with cycles and recurrences of the same point in a cycle. This is reflected in the title. "West" does not refer to the Occidental or European world or culture, but to the direction, for "Evening," and "Autumn" are conceived of as the same point on two different scales of the cycle of time, and both also correspond to the point called "West" in physical directions. This whole string of associations was inspired by Natsuda¹s view of a beautiful sunset viewed from an ancient temple in South Korea in 1995.