=California.=—­With the growth of the northwestern empire, dedicated by nature to freedom, the planting interests might have been content, had fortune not wrested from them the fair country of California.  Upon this huge territory they had set their hearts.  The mild climate and fertile soil seemed well suited to slavery and the planters expected to extend their sway to the entire domain.  California was a state of more than 155,000 square miles—­about seventy times the size of the state of Delaware.  It could readily be divided into five or six large states, if that became necessary to preserve the Southern balance of power.

Early American Relations with California.—­Time and tide, it seems, were not on the side of the planters.  Already Americans of a far different type were invading the Pacific slope.  Long before Polk ever dreamed of California, the Yankee with his cargo of notions had been around the Horn.  Daring skippers had sailed out of New England harbors with a variety of goods, bent their course around South America to California, on to China and around the world, trading as they went and leaving pots, pans, woolen cloth, guns, boots, shoes, salt fish, naval stores, and rum in their wake.  “Home from Californy!” rang the cry in many a New England port as a good captain let go his anchor on his return from the long trading voyage in the Pacific.

[Illustration:  THE OVERLAND TRAILS]

The Overland Trails.—­Not to be outdone by the mariners of the deep, western scouts searched for overland routes to the Pacific.  Zebulon Pike, explorer and pathfinder, by his expedition into the Southwest during Jefferson’s administration, had discovered the resources of New Spain and had shown his countrymen how easy it was to reach Santa Fe from the upper waters of the Arkansas River.  Not long afterward, traders laid open the route, making Franklin, Missouri, and later Fort Leavenworth the starting point.  Along the trail, once surveyed, poured caravans heavily guarded by armed men against marauding Indians.  Sand storms often wiped out all signs of the route; hunger and thirst did many a band of wagoners to death; but the lure of the game and the profits at the end kept the business thriving.  Huge stocks of cottons, glass, hardware, and ammunition were drawn almost across the continent to be exchanged at Santa Fe for furs, Indian blankets, silver, and mules; and many a fortune was made out of the traffic.

Americans in California.—­Why stop at Santa Fe?  The question did not long remain unanswered.  In 1829, Ewing Young broke the path to Los Angeles.  Thirteen years later Fremont made the first of his celebrated expeditions across plain, desert, and mountain, arousing the interest of the entire country in the Far West.  In the wake of the pathfinders went adventurers, settlers, and artisans.  By 1847, more than one-fifth of the inhabitants in the little post of two thousand on San Francisco Bay were from the United States.  The Mexican War, therefore, was not the beginning but the end of the American conquest of California—­a conquest initiated by Americans who went to till the soil, to trade, or to follow some mechanical pursuit.