This paper examines Cuci Parigi, a decennial ritual in Lonthoir village on Banda Besar Island, as a site for community reconstruction and cultural autonomy in postcolonial Maluku. Centered on the symbolic cleansing of a communal well, the ritual blends practical concerns with the reaffirmation of ancestral heritage and social identity. The study applies three interpretive frameworks. First, despite the loss of full clan genealogies, Cuci Parigi rearticulates ancestral authority through topogenic practices―ritualized narratives of place―allowing newcomers to be symbolically incorporated as "Bandanese." Second, it functions as a religious-cultural medium, fusing Islamic discourse with ancestral veneration by portraying founders as early bearers of Islam. Third, the participation of both Siwa and Lima alliance members enacts the Malukan principle of binary complementarity, turning past conflict into ritualized balance. In sum, Cuci Parigi illustrates the resilience of indigenous order and the generative power of ritual in shaping communal identity across space and memory in the Austronesian world.