During the period of intellectual revival in the sixteenth century, the custom of using eponymous terms arose, and the use of Latin as a common language enabled scholars throughout Europe to become familiar with each others writings and discoveries. Early medieval anatomists, such as Mondino de Luzzi and Berengario da Capri, introduced a systematic study of anatomy and dissection, and paved the way for Vesalius great work De humani corporis fabrica from 1543. After Vesalius, in particular Italian, Danish, Dutch and French anatomists studied human anatomy and their names are recognized in many eponyms. In the following centuries, German, English, French, Italian, Czech, Austrian, Hungarian and Russian anatomists greatly improved our knowledge of human anatomy. This resulted in the use of different names as eponyms in several languages for the same structure. More recently, also American, Japanese, Spanish and Swedish anatomists received their eponyms. In this Chapter, the major classical eponyms on arteries, bands, bodies, bundles, canals, corpuscles, ducts, fasciae, fibres, folds, foramina, fossae, ganglia, glands, ligaments, membranes, muscles, nerves, nodes, nuclei, plexuses, spaces, triangles, tubercles, valves and veins are summarized. Further data and illustrations on the various authors mentioned are provided in Part II The Anatomical Eponyms from A to Z. We did not restrict ourselves to anatomical eponyms but also included anthropological, embryological and histological terms. More recent, specific clinical eponyms are discussed in Part III Anatomical Eponyms in Clinical Disciplines.