Final answer:
Early Christian churches helped solidify the religious community by converting the Germanic peoples, preserving the classical tradition, and working with rulers to Christianize their populations.
Step-by-step explanation:
Early Christian churches helped solidify the religious community in several ways. Firstly, the institutional church, led by the popes, worked to convert the Germanic peoples to Christianity. This helped bring together different communities under a common religious belief. Secondly, the church played a role in preserving the classical tradition. Lastly, the church worked with new rulers to legitimize their rule and Christianize their populations, further consolidating the religious community.