What are three significant characteristics of the Renaissance in Northern Europe?

The Northern Renaissance developed characteristics distinguishing it from its Italian counterpart.  First and foremost, treatment of mythological subjects was very rare in Northern Renaissance paintings and sculpture.  Instead, Northern artists focused their attention on religious subjects; however, rather than celebrating Christianity, Northern works served as warnings, often taking on an austere or even a frightening appearance.  The work of Hieronymus Bosch, particularly the Garden of Earthly Delights (1510), illustrates humanity indulging in all manner of worldly pleasure, at the same time also indicating the result of such indulgence.  Comparing Bosch's Last Judgment to Michelangelo's Last Judgment from the Sistine Chapel clearly illustrates the different mindsets.

Unlike the Italian Renaissance, the Renaissance in the North did not change in response to humanism; instead, change was religiously motivated.  Thinkers in the North felt that Rome, physically distant from the North, had also distanced itself from the true Christian path.  This feeling brought about the events culminating in the Protestant Reformation.  The typically austere Protestant religious perspective is evidenced a great deal in the art of the region.

Beyond the subject matter, Northern artists generally preferred to consider color and the amount of detail in their works; they were more concerned with how the overall piece looked.  Perspective really does not develop in Northern painting until much later than it does in Italy.  For this reason, Northern paintings, with some exceptions, do not share the same sense of depth and are less spatially representational than Italian paintings.