The first picture discs of substantial size, sold as records meant only to be looked at and played, not put into a mailbox, appeared in the 1920s. Their first wave of significant popularity did not arrive until the start of the 1930s, when several companies in several countries began issuing them. Some were illustrated with photographs or artwork simply designed to be appropriate to the musical contents, but some graphics also promoted films in which the recorded songs had been introduced, and a few were blatant advertising that had little or no connection with the recording. Some politicians and demagogues explored the potential of the discs as a medium for propaganda. Adolf Hitler and British fascist Oswald Mosley were each featured on their own special picture discs.