Happy Michaelmas! Yes, today is Michaelmas, or the Feast of St. Michael and All Angels.
Here's a bit more information about it from our Tudor Society Feast Days ebook, which, like our other ebooks is free to members.
It was, and is, celebrated on 29th September, and was the feast day of St Michael the Archangel and Protector of the Church. St Michael is referred to as "the archangel Michael" in the Book of Jude, which tells of him "disputing with the devil about the body of Moses", and then the Book of Revelation tells of a war in heaven and depicts St Michael as leading God's armies against the dragon (Satan) and his angels, and defeating him.
The Feast of St Michael was officially the first day of the agricultural year, but sometimes coincided with Harvest Home, which marked the end of the agricultural year. Michaelmas was the time to prepare the fields for the next crop and it was also the time when accounts were done (now that the harvest was in and could be accounted for), annual rents were collected and bills were paid.
It was traditional to enjoy a feast of goose at this time of year. The geese had been fattened on the stubble land left over from the harvest and so were now perfect for slaughtering and cooking.
If you fancy cooking a goose, then why not check out this advice from BBC Good Food - https://www.bbcgoodfood.com/howto/guide/how-cook-goose