When Minamoto no Yoshitsune came back to Kamakura after defeat the Heike, he couldn't enter Kamakura, because he touched of anger in his brother Yoritomo. Yoshitsune stayed Manpuku-ji at Koshigoe. It is famous for the place where Yoshitsune wrote petition called Koshigoe-joe here.
Draft of Koshigoe-jo that Benkei wrote is on display in the main hall. However, whether really he wrote a petition is doubtful.
More importantly, many Kamakura-bori (Kamakura carving) are on display in the Hon-do (main hall) and Kori.