Sommarsblót (“Summer’s Blood,”) found at the very end of Ostara season, is a week-long festival happening sometime during Aries Season, ending on the day the Sun enters Taurus. Many sources mark this festival running from April 14-20th, but some sources say it is a moving feast and can happen any time during the first month after Spring Equinox.
Vikings and Norse folk, like many Celtic peoples, just cut the year into two halves. Sommarsblót also called Summer’s Finding, opens what we can call the “solar” half of the year (this is my name, and it’s probable that some other modern authors use this term as well. There is no historical precedent that ancient folk used this term.)
Norse folk, Vikings, and Anglo-Saxons all observed this festival that kicked off the high part of the year and celebrated the healing of the land from the harshness of Winter. Scandinavians would send messengers to the highest mountain peaks to observe the position of the Sun, to try to predict the date. As soon as the Sun spilled into the valleys, the great feasts would begin.