Historian: Fifteenth-century advances in mapmaking contributed to the rise of modern nation-states  In medieval Europe (from the fifth to the fifteenth century), sovereignty centered in cities and towns and radiated outward, with boundaries often ambiguously defined  The conceptual shift toward the modern state began in the late fifteenth century, when mapmakers learned to reflect geography accurately by basing maps on latitude-longitude grids
By the midseventeenth century, nearly all maps showed boundary lines
During the medieval period, various authorities in Europe claimed power over collections of cities and towns, not contiguous territories.