1. Who thought Americans were all gum-chewing gangsters?
Hansi's girlfriend, in Hansi, the Girl Who Loved the Swastika.
2. What Daredevil villain does the Batman villain the Masquerader resemble? Update: Resemble is the wrong word here; what I'm looking for is the DD villain that the Masquerader has the most in common with.
Both the Masquerader and the Gladiator started out as costume makers/tailors.
3. Whose favorite dish was Korala Stew?
Hawkgirl, aka Shayera Hol, loved her some Korala Stew.
4. What do the Blue Bowman and the Trapster have in common?
Both villains started out with different names. The Blue Bowman was originally the Signalman of Crime, while the Trapster was initially dubbed Paste-Pot Pete.
5. What happened during the Great Evolution?
This one goes back to one of the very first posts on the blog, about the Martian Manhunter's arrival on Earth in Detective #225:
As you can see, during the Great Evolution, all crime was supposedly wiped out on Mars. However, subsequent Martian Manhunter adventures cast doubt on that historical fact, as several of his stories featured criminals from Mars.
Jim got #1 right, while Kyle correctly answered #4, as did Blaze, who chipped in the answer to #2.