"The Big Four" was the name popularly given to the famous and influential businessmen, philanthropists and railroad tycoons who funded the Central Pacific Railroad (C.P.R.R.), which formed the western portion through the Sierra Nevada and the Rocky Mountains of the First Transcontinental Railroad in the United States, built from the mid-continent at the Missouri River to the Pacific Ocean during the middle and late 1860s.

Sacramento is the capital city of the U.S. state of California and the county seat of Sacramento County. Located at the confluence of the Sacramento and American Rivers in Northern California's Sacramento Valley, Sacramento's 2020 population of 524,943 makes it the fourth-most populous city in Northern California, sixth-most populous city in the state, and the ninth-most populous state capital in the United States. Sacramento is the seat of the California Legislature and the Governor of California.