Importance of Pony Express to Keeping California in the Union

It is of course a well-known fact that California never did secede, and that soon after the war began, she swung definitely and conclusively into the Union column. The danger of secession was wholly potential. Yet potential dangers are none the less real. Had it not been for the determined energies of a few loyalists in California, led by General E. V. Sumner and cooperating with the Federal Government by means of the swiftest communication then possible—the Pony Express—history today, might read differently.