Set in wooden type, in fact: the Hamilton Wood Type & Printing Museum in Two Rivers, Wisconsin keeps the obscure skill of wooden poster type and printing therefrom alive. (So can you, if you join: they offer studio access as a benefit of membership.)
Wooden poster type? It was the standard; most old posters (and even some new ones), especially the ones run off in huge numbers to promote events, were made with wooden type, offering huge flexibility in font and form.* It was cheaper than cast type, too. How good is it? Have a look at a nice topical example, and you tell me. (Plenty more in their store).
More about wood type can be found at the Rob Roy Kelly American Wood Type Collection at the University of Texas at Austin. It appears the very last commercial manufacturer held on until 2001.
* Windows users will find a parallel in Word: if regular typesetting is like normal typing in that program, wooden type is the Word Art utility.