21235
The Harzgau itself was first mentioned in a deed by the Emperor , Louis the Pious , from the year 814 , in which it was referred to by its High German form , " Hartingowe " .
 Harzgau, Louis the Pious, Hartingowe
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Harzgau, Louis the Pious, Hartingowe