Designed by architect Carlo Rainaldi and executed by many anonymous Roman artists and carpenters, the catafalque was an immense painted wooden construction, nearly reaching the flat ceiling of the basilica.
The windows of the basilica were covered and drapes hung from the nave's columns, with the intention of creating a rather eerie effect, although this is not immediately apparent from the accompanying engraving.
However, a contemporary report notes that during the hours of darkness the whole church seemed like "a serene night time sky in which shone many bright stars.
"[1] However, Philip IV died in Spain, so unlike traditional catafalques, the monument housed no cadaver.
A procession was held, ending at Santa Maria Maggiore, where a noted Jesuit, Ignazio Bompiani, gave an oration, accompanied by suitable music.