Savage took a wife, Eliza, and settled in Peru, Illinois. A daughter was born to this union. He and his brother, Morgan, were caught in the wave of California fever that affected many of the border settlements in the ’forties and they joined one of the overland parties in 1846. Lydia Savage Healy, another second cousin, expresses the opinion that the brothers joined Frémont’s third expedition. However, since it is known that Savage’s wife and child made the start, it is evident that they were with one of the parties of emigrants who, that year, made the journey. Mrs. Porter, then Sarah Seton, with two brothers and a sister drove from Princeton to Peru to bid them farewell. On this journey, “suffering and discouragement went hand in hand.” The wife and child did not survive the trip. Only the physically fit endured the hardships, and among these were Savage and his brother. By what route they entered California is not known, but S. P. Elias reports that Savage volunteered beneath the Bear flag and fought through the war against the Mexicans. A member of Frémont’s battalion, he was with Frémont both in Oregon and in California. After peace and before the discovery of gold, and shortly after the disbanding of Frémont’s battalion, he went to the south, settled among the Indians, and through José and Jésus, two of the most powerful chiefs in the valley of the San Joaquin, he established an intimacy with the principal tribes. By his indomitable energy, capability of endurance, and personal prowess he acquired a complete mastery over them to such an extent that he was elected chief of several of the tribes. He obtained great influence over the Indians of the lowlands and led them successfully against their mountain enemies, conquering a peace wherever he forayed. In any event, when Frémont and Pico put their signatures to the Cahuenga peace treaty on January 13, 1847, the Mexican War, so far as California was concerned, was at an end. Frémont’s battalion was disbanded, and we may believe, with Elias, that James D. Savage then established his intimacy with the principal Indian tribes of the San Joaquin. His aptitude for “picking up languages” apparently came to the fore, for he mastered the Indian dialect and extended his influence until it amounted to something of a barbaric despotism. The Indians acknowledged his authority, and he, no doubt, improved their condition. In the wars with the mountain tribes Savage’s tactics won them victories, and he brought about progress, generally.