It's also a tribute to José Guadalupe Posada (1852–1913), a Mexican cartoonist illustrator and artist. All the skeletons are his (I fancy them up a little bit). In spite of his work being nowadays associated to the day of the dead, it was meant to make a satirical point.
In Mexico, the Day of the Dead (el Día de Los Muertos), November 2nd, is a celebrating day. They not only homage their departed relatives making private altars and praying, but invite them to a special banquet. Fortunately, the living ones are invited too.
In Brazil, the Dia de Finados is a national holiday too, but, in general, we only go to the cemetery taking flowers to our friends and family members who have died. We also go to the church. However, most of us just enjoy the holiday and go to the beach.
The background is a Don Maples photo (Goldfield Ghost Town). There's a texture too, I've got on Deviant Art.