Adolph Bernhard Marx (1795-1866) may be the single most influential music theorist before Heinrich Schenker; he is also among the least understood. Although he is chiefly known today as the first to codify the elements of sonata form, Marx's four-volume Lehre von der musikalischen Komposition, praktisch-theoretish (1838-47) covered a wide range of subjects and was of enormous impact. But a full understanding of Marx's influence has been hampered by misinterpretation, often itself the result of mistranslation. Patrick Wood Uribe here offers close readings of Marx's writing as a corrective to these misapprehensions and re-evaluates the assumptions resting on previous readings. Among the results of his careful assessment is a new understanding of the way in which Marx's theories have shaped our understanding of sonata form. Uribe also counters recent scholarship that finds, in Marx's writings, the roots of the uglier side of German nationalism. A closer examination of precisely what Marx had to say, placed in its proper political context, absolves the theorist of a modern label that is perhaps over-reliant on hindsight.