The Primordial House System of Governance of Primaeval Niger Delta's Bonny Kingdom, enhanced by natural law, features as the bedrock of the civilization and good governance (GG) in the Kingdom. The Primordial House System of Governance of Ancient Grand Bonny Kingdom (Ibanise), which is comprised of present-day Bonny Kingdom and Opobo Kingdom, was originated and institutionalized by the Founding Ancestors of the Ancient Kingdom, led by three hierarchical categories of paramount natural rulers of the three tiers of government of the Kingdom, during the Kingdom's aboriginal era. The hierarchical categories are Ikpangi-Sibidapu (Institutionalized Lineage Heads), Amadapu (Community/District Heads and thus helpmates to Kings/Monarchs [Amanyanapu]), and Amanyanabo (owner of the land/King). The posts, positions or offices of these hierarchical categories, which have been in existence from time immemorial in Bonny Kingdom, are those of honour, traditional public service, trust, social responsibility and statesmanship, which were originated, systematized and institutionalized by the Founding Ancestors of the Kingdom towards the wellbeing of the people, Houses and entire Kingdom. This study employs socio-legal methodology to examine the Primordial House System of Bonny Kingdom and the role of natural law, namely proto-natural law, during the aboriginal era of the Kingdom, before Opobo Kingdom was established from it parent Bonny Kingdom, during the Kingdom's Civil War of 1869/70. It discusses the premier natural rulers of aboriginal Bonny Kingdom, as well as four generations of Okoloama Ingie KiriFajie, namely Bonny Kingdom (Ibanise), comprised of Fourteen Lineages/Families/Houses. On this note, from a historiographical background, the study makes a case for GG, fair play, social justice and harmonious ways of life in Bonny Kingdom, based on the good, transparent, responsible and accountable stewardship of traditional rulers, towards the wellbeing of the people and sustainable development of the Kingdom, particularly in the realm of apex, peak or paramount traditional rulership of the three tiers of government of the Kingdom, namely the Lineage, Country-House and overall Kingdom-wide tiers of traditional governance in the Kingdom. Besides, this study demonstrates how the aboriginal era of Bonny Kingdom underscores the Kingdom as a classic African primordial sovereign state and civilization, as well as a pride of Ancestral Ijaw nation, which contributed to the development and advancement of Primaeval Niger Delta region and beyond.