MorganGrayson - the middle comes from the old pagan and witches celebrations of the summer solstice where it is the end of the reign of the waxing year's Oak-King, who is now replaced by the Holly-King of the waning year (who rules until Winter Solstice). Also known as the fight between light and dark in some Pagan circles - as it falls on the longest day of the year - which makes it the shortest night
BTW it occurs in summer (around Jun 21) for the northern hemisphere - and around Dec 22 for the southere hemisphere
Good morning and happy link-bot checking