About tree frogs and man. Part 2: Historical distribution. Historical descriptions of the tree frog’s (Hyla arborea) habitat show that the species already inhabited small-scale agricultural landscapes in the 19th century. Opening up of originally forested landscapes by agriculture has probably led to improved possibilities for the tree frog, a species that prefers relatively warm and damp conditions. Originally, the species may have preferred living in peat bog landscapes which, in the Netherlands, could be found especially north of the rivers Rhine and Meuse. Historical records indicate that in the Netherlands the species was formerly especially present in the eastern and north-eastern parts. 19th century records of tree frogs in the southern parts of the Netherlands (but also in Belgium, the north of River Rhine) are more scarce, indicating that there may be an additional factor in play, viz. that populations south of the Rhine originated from specimens introduced there by man. In a third and last contribution this option will be explored.