Whilst most of Sebastiano's portraits were commissioned paintings which could be framed and hung wherever the donor wished, there were some which had a very clear destination. One of these installation pieces was the altarpiece that you find here. Such a project will present its own challenges, but also some very exciting rewards.
The artist chose to abandon his signature genre of should er-length single figure portraits in this instance, probably as a result of a request from the donor. They would have had a particular theme in mind for this altarpiece, but allowed the artist some room for artistic expression.
This compex scene features architectural features, a landscaped background, rough touches of perspective through the floor pattern plus the multitude of figures that are spread across the composition. It is likely that the landcape background was a depiction of the local region in which the altarpiece was to be placed.