The opening quote and some loose plot points come from the fairytale "Iron Hans".
This is the first episode in which Nick is shown writing his own entry in the Grimm Diaries about wesen.
With the exception of telephone calls, this is the first episode with action outside the Portland, Oregon area.
Renard recites the Latin proverb Si vis pacem, para bellum ("If you seek peace, prepare for war"), which was the motto of Deutsche Waffen und Munitionsfabriken, the manufacturer of the bullet Hank finds at the station. The 9mm bullet by DWM was also known as "Parabellum."
"Hundjäger" comes from the German "hund," meaning "hound," and "jäger," meaning "hunter;" given their jobs throughout history, likely meant to translate as "hunting hound."