I wonder if there are any connections to any of the old English customs like wassailing or ......
Of course. Many connections.
What are Gloshans, McT?
That's not so easy to answer (not that I provided a satisfactory answer above) but there was a pagan god in the Celtic tradition called Goloshan.
He was killed in the autumn by **** and was brought back to life, in effigy, in an annual ceremony. It's the old overwinter survival/ John Barleycorn/ evergreen plants folklore from the misty prehistory of the northern European peoples.
You can google the heck out of all of that: here's a fragment
This is the court of the Goloshan, the summer king with his retinue of performers, animal headed mummers and musicians. They claim Parliament Square as their own, transforming the space into a scene of merriment and rejoicing - not unlike after the Beltane procession reaches the bower!
Meanwhile, up near the Castle, the Cailleach and her own entourage gathers. This is a more sinister mob, bringing with them the dark energy of winter. With them is the Holly Lord, the Cailleach's consort and the winter aspect of the Green Man.
When the procession arrives at Parliament Square, the Cailleach's cohots run riot and break up festivities. The Holly Lord confronts the Goloshan and the two do battle with swords. The Goloshan is slain and the Holly Lord proclaimed victor. He then realises what he has done and bids the Cailleach to restore the fallen Goloshan, otherwise the continuity of the seasons will be broken. Following the resurrection of the Goloshan, there is much frenzied drumming and screaming as the Cailleach begins her reign and finally reveals her true self.