A thought crossed my mind though it's probably not a real reference I can't help but feel some connection between Ironborn culture and some biblical references. In the bible Samuel the Prophet searched for a 'godly man' to rule as king of Israel(doesn't it remind you of some other prophet who also said the king must be a man of god?), he also poured a flask of olive oil on Saul's head, similar to the Ironborn but with seawater instead. One last thing- the smallfolk and highborn alike sought the prophet's counsel and his words carried weight(they urged him to find a king) similar to the way the lords of the Islands seeks Aeron's advice on who should rule after Balon. Coincidence? well, yeah probably haha but still, interesting thought no?