The Montagues and Capulets are two prominent families in William Shakespeare's play, Romeo and Juliet. They are known for their long-standing feud, which creates a backdrop of conflict throughout the story. This rivalry affects not only the families but also the entire city of Verona, leading to violence and tragedy. The feud between the Montagues and Capulets is central to the plot, as it prevents the young lovers, Romeo Montague and Juliet Capulet, from being together. Their love ultimately challenges the hatred between their families, highlighting themes of love, conflict, and the consequences of familial loyalty.