Half a century after the first work on the Romanian Roms written by M. Kogălniceanu (1837) at the suggestion of the father of modern geography, Alexander von Humboldt, similarly, at the suggestion of a foreign scholar, the father of Romani dialectology, Franz Miklosich, a graduate of the Faculty of Theology, University of Leipzig, and Ph.D. of the same university, Barbu Constantinescu, started to learn Romani and became the first Romanian scholar in the emergent field. He was an acknowledged educationist, the first exponent of Herbatianism in Romania, and worked in many educational pioneering projects, such as the establishment of the first kindergarten, as well as the reformation of the pedagogical and theological systems of education. In the field of Romani studies, unfortunately, he could not publish all his projected work, and posterity forgot his huge effort of travelling in all counties of Wallachia and Moldavia in search of Romani settlements. He published in Bucharest, in 1877 and 1878, a dozen songs and tales in Romani of his own translation, which were duly acknowledged (e.g. by F.H. Groome in his 1899 anthology of Gypsy folk songs). However, his work, comprising hundreds of documents, was not included in a collection, though it is partially preserved in some unedited manuscripts at the Romanian Academy Library in Bucharest, which are described here for the first time, in sections § 2.1–6. The article describes the intellectual legacy left by Barbu Constantinescu in the field of Romani studies.