inaccurately, call the Protestant Cemetery in Rome. Jews and members of the Russian Orthodox Church are laid there, as well as Protestants. There are also atheists, such as Shelley, who had his son William buried there before Keats, and, not long after, Shelley's own ashes. Henry James's friend Constance Fenimore Woolson, who committed suicide, also asked to be buried there (and was).
It is the most lovely cemetery I know, and owes its origin to the intolerance of the Catholic church, which forbade all non-Catholics burial in consecrated ground.