where did the office of Commander in a Royal Ark Mariner lodge come from and what are the actual duties expected of the brother in that chair

The degree of Royal Ark Mariner originated among eighteenth-century operative Masons as a side degree 1, with early references recording a Grand Lodge of Royal Ark Mariners reconstituted in 1772. Following a period of obscure early history, the Order came under the jurisdiction of the Grand Lodge of Mark Master Masons in 1871, which purchased full rights to the degree in 1884, leading to the structure where a Royal Ark Mariner lodge is attached directly to a Mark lodge 1. Under this administrative framework, the lodge is governed by a Worshipful Commander rather than a Worshipful Master, as the Grand Lodge of Mark Master Masons records.

The Worshipful Commander governs the lodge, presides over its business affairs, appoints and invests the officers of the lodge, and conducts the elevation ceremonies for candidates entering the Order, as the Grand Lodge of Mark Master Masons details. Upon installation according to ancient usage, the Commander elect receives a current copy of the Constitutions and Regulations. Qualification for election to the chair requires that a brother must have served one complete year—from one installation meeting to the next—as either Senior Warden or Junior Warden in a regular Royal Ark Mariner lodge, and he must also have been installed as Worshipful Master of a Lodge of Mark Master Masons, according to the Grand Lodge of Mark Master Masons.

The ritual is founded directly on the biblical account of Noah's Ark, the Deluge, and the Dove 2. In eighteenth-century practice, candidates and members of the Royal Ark Mariner degree professed to be followers of Noah, calling themselves Noachidae or Sons of Noah 2.

The governance and terminology of the degree were historically structured around Noah's leadership. The presiding officer was designated with the title of Grand Noah, while the lodge assembly was called a Royal Ark Vessel 2.

The visual regalia and lodge symbolism explicitly depict the events of the flood, featuring rainbow sashes and aprons embellished with images of the ark and the dove 2. Early songs associated with the degree recounted the narrative of Noah building and entering the vessel, floating safely upon the waters when the deluge arrived and heaven shut the door 2.

In broader Masonic tradition, the identity of the Noachidae is linked to the seven traditional Precepts of Noah, which include worshipping God, practicing justice, and abstaining from murder, theft, and idolatry 2.