Arcadia, the central plateau of Peloponnesian peninsular, was in ancient times inhabited by shepherds and hunters, who worshiped Pan, god of flocks and herds. In literature and art Arcadia was idealized and turned into a pastoral paradise ruled by Pan and inhabited by carefree shepherds and shepherdesses, Nymphs, and Satyrs.
The phrase Et in Arcadia ego, which could be found inscribed on some paintings, means ‘even in Arcadia I (i.e. Death) am to be found’, that is even in the earth paradise one can't hide from death.
See: Nicolas Poussin. The Shepherds of Arcadia, The Shepherds of Arcadia.