+1421 marked a year in the [15th Century](/wiki/15th_Century), a period of transition within the [Late Middle Ages](/wiki/Late_Middle_Ages). Across the globe, empires shifted and new ideas began to emerge.
+## See also
+- [Middle Ages](/wiki/Middle_Ages)
+- [1420s](/wiki/1420s)
+- [Julian Calendar](/wiki/Julian_Calendar)
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