The Hidden Trellis: Where Does the Second Group Begin
in the First Movement of Beethoven's Eroica Symphony?

by William Horne

For a long time, distinguished and thoughtful analysts have parsed the exposition of the first movement of the Eroica Symphony in strikingly different ways, especially with regard to the beginning of the second group (ex.1). In a widely read text, for example, Leon Plantinga writes:

After unarguably establishing the tonic key of Eb with two statements of the opening motive (mm.3 and 15), Beethoven feints toward the dominant (mm.18ff.), only to reestablish the original key in m.37 with another resounding assertion of the original melody. In m.45 an abrupt shift is made to the dominant Bb in conjunction with contrasting new material, but we are not yet allowed to rest comfortably in the new key; the active, brilliant, modulatory passage beginning at m.65 sounds exactly like bridge material, and its inexorable conclusion in Bb (m.83) establishes this point as the "real" beginning of the dominant key area. From here to the end of the exposition no other key challenges the supremacy of Bb.