The display in the two rooms which together make up the Hall of the Animals was set up under Pope Pius VI (1775-1799) with antique works of art, often much restored and sometimes completely re-worked, with the aim of creating a 'stone zoo'. Many artists worked on the sculptures in this display during the 1700s, the most important of whom was Francesco Antonio Franzoni.
For the displays were chosen works of art selected for their links with nature and the chase. In this Hall it is the animals who are the protagonists, and can be seen both in curious interactions between one another, and also in relation to heroes and gods of the ancient world. Coloured marbles were used to allude to the colours of the coat or plumage of various animals or, by contrast, to confer a particular colouristic effect on a work of art.