Folk religions, filial piety, reverence for ancestors, and the “three teachings”—Confucianism, Daoism, and Buddhism—formed the belief systems of ancient China. Tenets from each informed daily life, and no single doctrine persistently dominated. Confucianism became the virtual creed of imperial China in the Han dynasty and concerned itself with respect for fellow humans and such practical affairs as the organization of government. Daoism focused on establishing harmony between human beings and the natural world and was at times politically influential. Buddhism arrived in China from the west along trade routes and blended with existing teachings, becoming extremely influential before suffering harsh persecution during the Tang dynasty. The vital mixture of the three systems in the private, political, and religious spheres is vividly reflected in the tomb arts of the Northern Wei (386–535 CE), Northern Qi (550–577 CE), and Tang dynasties (618–907 CE).