Most refused inoculation. Frederick of Prussia wrote to Catherine urging her not to take the risk. She replied that she had always been afraid of smallpox and wished more than anything to escape this fear. In May 1774, almost six years after Catherine was inoculated, smallpox killed the king of France. Louis XV took to bed a barely pubescent girl who was carrying smallpox. He died soon after, ending a reign of fifty-nine years. His successor, nineteen-year-old Louis XVI, was inoculated immediately.