In the instance of St. Peter's Basilica this loss has primarily been the result of the papal throne being moved from its traditional location beneath and before Bernini's Altar of the Chair (which location was also symbolic, tying relic of the Chair of St. Peter himself to the throne or chair of the Roman pontiff, his successor) to its current location before the main altar., over the confessio However, in other instances, such as papal Masses in the Sistine Chapel or outdoor papal Masses, this elimination is more of a question mark since they certainly could be continued to be used in those particular locations. Whatever the reasons, our focus today is simply on the tapestries themselves.
It is not extremely easy to pull up a great deal of information on these as certainly the Vatican has commissioned any number of tapestries, so by no means is this article intended as a detailed, scientific history of these tapestries; it is rather more a case of taking a quick but focused glance at how some of these were used.
In this first instance, seen also above, we see an image taken from the outdoor Mass of the papal coronation of the Pope Paul VI. So it was for this particular occasion the tapestry that is selected is that showing Christ giving the keys to St. Peter -- which of course, obviously is well suited to this particular Mass, coming with reference to the Petrine mission as the Vicar of Christ.
Next we have a consistory, this time coming from the time of Pope Pius XII. For the consistory which saw the creation of new cardinals we see used here a replica of the tapestry of Clement VII which shows three of the cardinal virtues (Prudence flanked by Justice and Charity). No doubt there was a specific symbolic reference here to the role and mission of the college of cardinals and the cardinal virtues themselves.