It turned out that this was in fact the Festa della Rificolona. A Florentine tradition that dates back hundreds of years. Now I am not entirely sure what it is for or what they are all celebrating, maybe something to do with the Virgin Mary.... Anyway it was really lovely as all the little bambini (children) get to carry around these pretty lanterns and hold them high above the crowd. All the while other children bearing pea shooters try to break surrounding lanterns with an awful lot of huffing and puffing involved. Being tall and also stuck in the centre was not great as I too seemed to get peppered by various tiny objects.
The march weaved its way through the historical centre of Florence before finishing in Piazza della Santissima Annunziata where there was a stage waiting with lots of speakers and another crowd clapping in the parade. I'm not sure if the lanterns were meant to be set fire to but that did not stop a few going up in flames within close proximity to me causing a bit of a panic! Then, on stage, a man who I think was the Mayor spoke to the people gathered with great gusto and waving of arms, cue much clapping. They even got this old woman up on stage to present her with a prize of the best lantern. Bless. It was quite good actually. A mini model of the Papa. Cue more applause. Luckily I think mini Pope managed to survive the night without going up in flames!
So all in all a rather fun evening. Bit odd, but these surprises come hand in hand with living in a foreign country for a year.