Where do atheists get their morality from?

[Red Celt]

The ancient history of China was much the same. For a few thousand years, until sometime in the first millennium BCE, Chinese spiritual practices focused on divination, practiced by shaman, in order to help the people arrive at a "fortunate" (lucky) result to their plans, hopes and dreams. There was nothing moral about it. It was reading of bones and tea leaves.

The Spring and Autumn period gave rise to a blossoming of religious philosophies, but these philosophies took no heed of the growing practice of god worship, and were largely secular in nature. To call these systems "religious morality" in the Western sense associated with the Semitic religions would result in the grossest of distortions.

Tsze-kung asked, saying, "Is there one word which may serve as a rule
of practice for all one's life?" The Master said, "Is not Reciprocity such a
word? What you do not want done to yourself, do not do to others."

— Confucius, Analects XV.24