The phrase "on the warpath" is often used to describe someone who is angry or aggressive, and looking for a fight. The antonyms for this phrase would be words that describe someone who is calm, peaceful, and not looking for conflict. Some possible antonyms for "on the warpath" might include "tranquil," "serene," "composed," "harmonious," "reconciled," or "placated." These words suggest a sense of balance and contentment, rather than the agitation and unrest implied by the phrase "on the warpath." By using these antonyms, we can describe people who are opposed to violence and seek to promote peaceful resolution of conflicts.