The "Ancient Grudge" between the Capulets and Montagues

In my opinion, the “ancient grudge” between the Montagues and the Capulets seems to be something which has been going on for a long time and has died down. The reason they hate one another so much is unclear throughout the play, and is never explained. Furthermore, besides the early battle in the beginning of the play, there does not appear to be much of a grudge between the majority of the two households. In addition, Old Capulet knew of ...