They come;
those Viking spirits
on the lapping ancestral waves
of memory and myth.
They conquer hearts for the day,  
proclaiming a time for turning.
Torchlight gives way to flame,
which turns to fire,
transforming heat with real warmth,
licking upwards, giving light.
flickering sign of a turning world
looking forward now to lengthening days
as Lent, the Springtime of the year,
draws us forward with new expectation.

[Mr G]

This poem is inspired by the annual festival of Up Helly Aa, held at Lerwick on Shetland , each year on the final Tuesday of January. It marks the end of the Yule, or Christmas, season which was kept, under the old Julian Calendar at this period of the year. According to an article in Wikipedia, Up Helly Aa means, literally Holy Day.
The Festival draws from the link between the Shetland Islands and Norway of which it used to be a part. So it centres on a replica of a Viking Longship. It is ‘crewed’ by locals dressed as Vikings knows as Guizer Jarls (pr. Yarl) with a head Guizer presumably as warrior captain. Each Guizer is dressed in a figure from Norse legend. This year for the very first time, these include women and girls, though a few have slipped in many years ago disguised by costume!
After a day of festivity, as night falls, the replica Longship is dragged through the streets of the town in a procession led by torchbearers. The Longboat is circled by the torchbearers who then sing a traditional song associated with the Festival. They then cast their burning torches into the ship which lights up the night with fire. Once the ship is just embers, another song is sung and then it’s party time as the people sing and dance the night away.

The following day is a holiday or ‘hangover’ day!

The Festival marks a transition from Winter Festival towards the season of Lent. In Christian terms this is also a turning point as we begin to prepare for the Passion, death and Resurrection of Jesus at Eostre, Easter.
Lent itself is Old English for Spring. It is a time of growth as the earth gives birth to new growth. This growth is both spiritual as well as physical. It carries new hope and new expectation for each of us and for our world. And don’t we need it!

[There are a number of informative and entertaining sites about Up Helly Aa on the web. The photo is from one of the official sources]