A rather extensive study of more than 240 herbarium collections from the Amanita caesarea-complex from Mexico, the Eastern U.S.A., Canada, Europe, Africa, and Asia provided the basis of the present work. Amanita caesarea and A. hemibapha, both sensu auct., are misidentifications of several species. Amanita caesarea s. qtr. is unknown in the U.S.A. and Canada, but it grows in Mexico, although it is a rare fungus. Amanita hemibapha s. qtr. is unknown in America. All the Mexican species of this complex have a great traditional and economic importance as foodstuff, also in Guatemala. A list of more than 60 common names in Mexico and Guatemala is provided, several of them in Indian languages. A critical revision of taxonomic features is discussed. Color, form, and striation of pileus and length, color and desquamation of the stipe are the main macroscopic features, and spore size, and subhymenium sickness are among the main microscopic features. The A. caesarea-complex belongs to Section Caesareae and is formed by at least 13 species. This complex is divided in Stirps Caesareae (with A. caesarea s. qtr. as the type) and Stirps Hemibaphae (with A. hemibapha as the type), according to the thickness of the subhymenium (3-5 cells thick in the former and 1-3 cells in the latter). Species in the Stirps Caesareae here described besides A. caesarea are: A. basil sp. nov., A. tecomate sp. nov., A. tullossii sp. nov., and A. yema sp. nov. Species in the Stirps Hemibaphae here discussed are: A. arkansana, A. caesareoides, A. hemibapha, A. jacksonii, A. Iaurae sp. nov. A. mafingensis, A. masasiensis, and A. tanzanica, of which A. jacksonii and A. Iaurae are full described. A key with all these taxa is presented.