Well back at Hallowe'en I promised to write about midwinter. And here we are! And I've nothing prepared! Despite nearly two months lead time!
Well here's a rotating animation of the earth viewed from the sun at (Northern) Winter Solstice, illustrating the whole long night/short day thing. You can also see what it's like in other parts of the world.
Wikipedia notes that the word solstice comes from latin; sol meaning sun and sistere, to stand still. Thus the solstice is where the suns stands still for a moment in it's North-South movement across the fixed stars.
As might be expected, the solstice was an important time for the later roman cult of Sol Invictus (the undefeated sun). This cult was also associated with the cult of Mithras and celebrated the festival on the Winter Solstice of the Julian calender; 25 December. Converts to early Christianity kept this festival, equating Jesus with Sol and/or Mithras, and holding a mass in his honour. This was condemned by the early Catholic Church for being a pagan practice.
Midwinter is traditionally the start of the deep winter and the famine months of January through March; famine months as no new food was available to pre-modern communities.
Anyway, if you're reading this, you probably want Stonehenge, neopagans singing and Druids. Where are the Druids? I can hear you ask. Henge at Winter Solstice. Druids.