The phrase "is ruled by" refers to the concept of a person, group, or entity controlling or governing a specific area or population. Some potential synonyms could include "governed by," "dominated by," "controlled by," "guided by," "commanded by," or "managed by." Each of these phrases conveys a similar idea of one entity having power over another, with varying connotations of the degree of control and influence exerted. When considering synonyms for "is ruled by," it's essential to consider the nuances of meaning and context to select the most appropriate phrasing for the intended message.