TROPO. — An ornament of liturgical chant by interpolation or addition, which thereby tends to embellish it by lengthening II. This is especially true of the musical t. The literary t., following the popular tendency, fragments an earlier melody—primitive or itself added—into syllabic chant.
It seems that originally the word t. was synonymous with melody (e.g., in Fortunatus), whence the expression «trepi carminum», designating the chant accompanying passages of added verse (MS S. Gallo 484). Although it is certain that in Gregorian chant the t. is found toward the end of the ninth century, its origin is not easy to determine. S. Gallo and S. Marziale di Limoges were the first two important centres of a practice that rapidly spread to all countries, and t. were soon found in all liturgical chants, in the parts of the Office, and in much greater number in those of the Mass, except for the Gradual, which is rarely troped. A customary distinction is made between great t. (those of the Kyriale) and small t. (those of the Proper of the Mass). It is also said that even readings (Epistles) are troped, and that t. were eventually introduced into the t. itself (e.g., Regnum tuum solidum). The t. of the Gloria in excelsis received the name Laudes. Whatever one may say, there must be a certain connection between these Laudes, these t., and the Laudes festivae, or acclamations, which accompanied the Gloria. Just as the Laudes festivae are not, neither is the Versus properly speaking a t.: it is a poem whose syllabic chant accompanies a procession; it thus comes to be joined to the Introit, for which it serves as an introduction. But it played a major role in the history of the t., since its structure guided its evolution toward a poetic form, at first assonant (t. of the first period, up to 1070–80), then rhymed and increasingly independent of the liturgical text (t. of the second period). Thus one can understand what a troped Office could be in the thirteenth century; the manuscripts give some idea of it, since the festive Mass alone occupies five or six times as many pages as the simple Gregorian text. As a result of this development, the meaning and beauty of pure Gregorian melody remained misunderstood: the t. bear witness to an evolution in taste and also in piety, and to the pleasure taken by clergy and faithful in lengthy ceremonies. On the other hand, this movement of the t. subsequently gave rise to more recent art forms: from the t. arose the sequence, then the song in the vernacular, popular song, or the poetry of the troubadours (v.); from the t. also derive liturgical drama and, through medieval theatre, modern opera. The t. likewise provided material for the earliest polyphonic compositions.