St. George's Day is the National Day of England. In myth, St. George was a dragon-slayer, in reality, St. George was a Roman soldier who stood out against the Roman prosecution of Christians and eventually died for his beliefs.Blessings,
Sigurd's Day is also held on the National Day of England, dedicated to Sigurd, or Sigeweard, who hails from Norse Mythology. Sigurd was a dragonslayer, who becomes a Dragon-lord.
Unfortunately, I couldn't find much info on how Sigurd's Day is celebrated. But St. George's day is mainly just observed as a Bank Holiday now.
Sources:
http://www.woodlands-junior.kent.sch.uk/customs/stgeorge.html
http://www.wodensfolk.org.uk/ritual.html
Petra