Claude Le Jeune (born at Valenciennes , ca. 1528; died at Paris, 1600) was a towering figure in French Renaissance music. In spite of this, few biographical details have survived the turmoils of his time , which was marked primarily by the Wars of Religion, the last years of the reign of the Valois, and the struggle of Henry IV for the crown of France. In order, therefore, to attain a more complete picture of Le Jeune's life and work, the general historical and spiritual background, circumstantial evidence, is considered more implicating much intensely than usual. The two dominating beacons in Le Jeune's life are his allegiance to the Reformed Faith , involving close connections to leading Huguenot figures, and his inclination towards Humanism, confirmed by his association, from 1570 onwards, with the Academie de Poesie et de Musique of Jean-Antoine De Baïf. The present study is concerned with the initial years of Claude Le Jeune, covering the thirty- seven years of his life from 1528 (the assumed year of birth) intil 1565. In terms of publications, this period includes his "youthful" works : four early chansons from 1552, the Dix Pseaumes with a dialogue for seven voices , Mais qui es-tu,of 1564, and a single motet à 3, Nigra sum sed formosa, published in 1565. The background of his northern homeland is screened with particular attention to the involvement of the members of the Le Jeune family in the religious affairs of the time. Also the general cultural and musical milieu of the Netherlands is investigated within this and Le Jeune's first published works are considered biographical framework. These works still bear the stodginess and gaucheness of an apprentice. The probability of a sojourn in Italy is explored with positive findings. This visit most likely brought Le Jeune within the circle of the ageing Willaert at Venice, Major focus is placed upon the Dix Pseaumes, the first comprehensive collection to appear entirely under Le Jeunes ' s own name and dominating the initial period of his creative life. Detailed analyses reveal the hand of a now asserted composer. well-versed in technical matters and in possession of a fine perception for both the tenets of Calvinism and the aspirations of musical Humanism . As far as the latter is concerned. pertinent attention is given to its roots in the rhetorical and philosophical traditions. and how Le Jeune accommodated issues which sprouted from these and occupied the theorists of his time. Musical text expression holds. since the Dix Pseaumes. a central place in Le Jeune's works in which he maintains a fresh and subtle approach steering clear of the dogmatism of some contemporary theorists. Using various musical devices (modes, chiavette, melody, rhythm, harmony, texture, and even structure) to serve text expression. Le Jeune' s parlance gradually develops a currency in its own right. often expressing the meaning or implication of a text more comprehensively than can be attained by means of a linguistic medium. Appropriate to this particular trait of development in language. recognition is given Le Jeune's musical language. Included into the discussion are concordances of works by other composers where these exist as well as references to the relevant musical topography. A concluding summary of the moulding forces in the initial years of Claude Le Jeune's life as well as the gradual formulation of his distinct musical language concludes this study which can be regarded as an introduction to a more comprehensive programme of research on the life, times and works of Claude Le Jeune, Huguenot and Musical Humanist. A general bibliography is included while the folling appendices are included. 1 . A Bibliography of the works of Claude Le Jeune (all printed editions from 1552-1775). complete with descriptions . text incipits. sources. and class nubers; 2 . some relevant documents; 3. the literary texts of the works discussed; and 4. the "youthful" works. all of these (except the chanson spirituelle. Mais qui es- tu,as yet not republished . Various portraits. maps and other relevant illustrations are intended to enhance the presentation.