Since it is Ganesh Chaturthi – an extract from ” GHOST DIVISION – On The Bhutagana Of Mahadev & The Einherjar Of Odin ” that is particularly relevant; which helps to explain both one of the roles of Lord Ganesha – as well as the underlying symbolism of His Elephantine Head:
The Gana As Custodian Guard
Yet while Skanda is regarded as the ‘Lord of War’, and therefore the ‘Supreme Commander’ in a military sense of the Armies of the Heavens [a position which, in the Nordic end of things, would be held by Odin – as Herjan, Hertyr, Hergautr, etc.]; in terms of a Lord of the Host, that title may be more directly affixed to His Sibling – Ganesha.
Not least because, well, that’s what the Deific Theonym in question directly translates as: Gana-Esha [‘Esha’ meaning ‘Lord’]. Further conceptual support for the linkage of Ganesha with the Ganas, can be found in various of the myths surrounding Ganesha; and in particular, the much-retold legend of how He came to bear an Elephant’s Head.
As the story goes, Parvati had placed Ganesha on guard-duty outside a location where She was bathing. Shiva arrives, and seeking His wife, proceeds to attempt to enter; whereupon He is challenged by the child – which, for some reason, He does not recognize. In an incandescent mood, Rudra then decapitates the sentinel, and goes in anyway. Parvati, upon realizing what has happened to Her Son, is understandably irate; and berates Mahadev for His action. Shiva, distraught and remorseful at what has occurred, arranges for a replacement head to be procured and attached, which turns out to be that of an elephant.
Now, according to some sources, Ganesha then acquires the title ‘Ganapati’, understood as ‘Lord of [all] Creatures’, at this point, as part of the ‘rehabilitation’. But I’m not sure if that’s quite what’s gone on here. You see, the role little Ganesha was carrying out when the decapitation occurred, was that of a sentinel – a guardian, a watchman standing in warding of His Lord (or, in this case, Lady). This is an absolutely prime function for a warrior in the retinue of a King; and therefore, I am of the opinion that this pre-eminent upholding of Duty, even in the face of what must have been the absolutely terrifying nature of an encounter with a lethally enraged Lord Shiva, must have been what induced the application of the GanaPati appellation. That is to say – Ganesha is Named as the Chief of the Ganas, as He is shown and seen to be of the highest resilience and resoluteness in the carrying out of one of the prime Duties of the Gana of Mahadev. That of Guarding, of Standing Watch over the Divine Couple (whether singly, or in partnership of Each Other’s blessed company), and of holding the entrance.
You can see how this leads directly into Ganesha’s portfolio responsibility as God of Entrances/Gateways/Doors/Openings. Hence why at Hindu Temples, you will customarily see a small (or, in some cases, (very) large) Ganesha positioned strategically at the entryway. Thus simultaneously showing that the Mandir is under the Protection of the Gods; and also, interestingly enough, carrying out a ‘filtration’ process of keeping out the “unworthy” (and therefore, from the direct Presence (in the Murtis, and radiating out, inter alia) of the Gods in Their Dwelling Therein). I say “interestingly enough”, because you may recall the earlier citation for exactly this, as a prime purpose of the Ganas in Their accompaniment of Lord Shiva into the Cremation Ground.
The selection of the motif of the Elephant’s Head, contra to some of the mythological accounts in this direction, can also have been no accident. After all, if we consider the traditional associations of the Elephant within the context of Hindu Iconography – that of mental faculty, of serious capability of force, and also of regality and royal power – it would make absolute sense for these to be visualized in connection with the retinue, the Royal Guard, of the God-Emperor. This becomes exceptionally the case in light of the other associations of the elephant – strong faculty of memory (a pretty important skill for the supernal sentinel, especially given the elephant’s ability for facial recognition and other such identifiers), and being very, very protective of their Graveyards.