 As a consequence, cartographers and historians have described those kingdoms both as realms of Charles V and as possessions of Ferdinand, not without confusion.Others, such as the Venetian enoys, reported that the states of Ferdinand were "all held in common with the Emperor".Therefore, although he had agreed on the future division of the dynasty between Ferdinand and Philip II of Spain, during his own reign Charles V conceived the existence of a single "House of Austria" of which he was the sole head.