The inauguration was originally held in March for two reasons — it took longer for news to get out in the 18th century, and also because the position of the sun on that day forms a trine with the position of the sun on Independence day — the founders were masons who were highly informed about astrology (Washington signed the accord with Cornwallis at a specific propitious hour and minute).
Huh. I don’t think I knew of the Masonic aspects.