On the protesters’ signs and banners, a new symbol was making its first appearance. Gerald Holtom, a designer and a pacifist, had developed it specifically for the march just a few weeks prior.

At the very beginning of the “Symbol Sourcebook: An Authoritative Guide to International Graphic Symbols” (1972), the book’s author and one of the era’s most accomplished industrial ...

Next to the portrait of Odin was a small swastika-like sign, once a signifier of peace, wealth, and fortune. Today, the swastika is seen by many as a symbol of hatred, extremism, and danger.