The reception of Fryderyk Chopin's works, both in musical life and in literature, has changed during over 150 years since the composer's death. An example of this is the degree of popularity and the assessment of Chopin's two highly contrasting polonaises Op. 40. One, inA major, enjoyed immense popularity in the nineteenth century. It was often performed both at public concerts and at homes and private salons. There were also numerous transcriptions of it. The other, inC minor, was rarely played in public and there is no information about it being performed in private homes. Nor were there any transcriptions of the piece.Their disparate popularity was accompanied by diametrically different evaluations of the two pieces. ThePolonaise in A majorwas highly valued in the nineteenth-century musical literature and regarded as one of the best or by many authors as Chopin's best polonaise. It was believed to contain scenes from Poland's knightly past. ThePolonaise in C minorwas clearly underestimated and regarded as Chopin's less successful piece. It was only Friedrich Niecks who was the first author to appreciate this Polonaise and it was only then that a gradual change in the assessment of the two works began.The causes of the nineteenth-century judgments and changes which took place later lie in the structure of each of the works. ThePolonaise in A majorclosely follows the convention of the genre, it contains distinct connotations with popular music, practical dancing and with popular patriotic songs. ThePolonaise in C minordefies the convention of the genre, breaks the existing norms, and the musical means it uses are far more refined and go far into the future.It appears that it was not the very fact of departure from the convention that determined one or other nineteenth-century assessment of a work but rather whether and to what extent this departure from the convention was compensated for by the use of musical means which had the easiest and most direct effect on the listeners' senses, such as sharp contrasts, expressive melodic patterns, dynamism and strong tensions. This is shown by thePolonaise in A flat majorOp. 53, which, despite the fact that it departs from the then conventions of dancing and has a novel form and rich harmonics, was one of Chopin's most highly regarded and most often performed works. ThePolonaise in C minor, while departing from the convention, is devoid of dynamism at the same time, its nature being more static, the piece being largely based on a play of tonal nuances, and thereby it was far more difficult to accept. It was only later changes that took place in music that allowed it to be understood.