Complex sentence: Thus, it was also mostly history painting, that marked Blunck's early work until, through genre painting, it became representative of the kind of everyday realism, that was to appear in danish art in the mid 1820's.
Split into simpler sentences: Thus, it was also mostly history painting, that marked Blunck's early work. Later, through genre painting, it became representative of the kind of everyday realism, that was to appear in Danish art in the mid 1820's.