In the Western tradition the North Node is the Dragon's Head, or Caput Draconis, a Latin rendering of the Arabic dragon-head concept that entered European astrology through translations of Arabic and Persian sources in the medieval period; the ninth-century scholar Abu Ma'shar discussed the node under this dragon framework in his widely translated writings.
In Indian astrology it is Rahu, drawn from a distinct Vedic myth in which the demon Svarbhanu drank a share of the gods' nectar of immortality and was beheaded by Vishnu for the offense, leaving an immortal head, Rahu, and an immortal tail, Ketu, that were placed in the sky as the lunar nodes. Its glyph, resembling a horseshoe or an upturned loop with two feet, appears already fixed in form in medieval Byzantine manuscript copies of ancient horoscopes, indicating a symbol whose specific design is old even where its very first use cannot be dated precisely.
Modern astrological software and printed ephemerides have kept this same loop-and-feet form essentially unchanged, so that a chart drawn today uses a glyph whose lineage can be traced, if not to a single inventor, then at least to the same manuscript tradition that carried the rest of the classical astrological symbol set through the medieval period.