Final answer:
The governing philosophies shifted from Confucianism to Legalism due to Legalism's emphasis on power, practical politics, and the need for a strong government in the face of interstate competition. The rise of the state of Qin and the practice of Legalism reshaped popular religion and influenced the elite ruling class.
Step-by-step explanation:
The governing philosophies shifted from Confucianism to Legalism due to several factors.
One reason was that Legalism emphasized the accumulation of power through a written legal code and a system of rewards and punishments to ensure order and enforcement. Legalists believed that a strong army and a wealthy country were the foundations of a good government.
Additionally, the Warring States Era and the rise of the state of Qin played a significant role in the shift to Legalism. The state of Qin adopted Legalist reforms to justify its agenda of power and expansionism. The Legalists' focus on practical politics and their belief that people act only in their self-interest appealed to rulers seeking to consolidate their power.
Finally, the emergence of Legalist government practice over four centuries reshaped popular religion. Legalism became widely adopted and influenced the culture, including the elite ruling class. Confucianism, on the other hand, emphasized morality and family practices, which became less appealing to rulers in the face of increasing interstate competition and the need for a strong centralized government.