Contra Costa County administrative offices are located at 651 Pine Street, Martinez, CA 94553; phone: 925‑335‑1080.
The first American settler in Contra Costa was Doctor John Marsh. He achieved much distinction from his letters and descriptive articles, which gave a graphic portrayal of the primitive conditions as he found them. To his facile pen California historians, and Contra Costa Historians especially, are indebted for much of their data relating to the early period.
Doctor Marsh was descended from an old New England family, and was a graduate of Harvard College. Born in Danvers, Massachusetts, in 1799, he came west and conducted a mercantile business in St. Joseph, Missouri from 1828 until 1835. During the latter year he started on horseback for the Far West, eventually becoming one of an exploring party which visited the Mexican states of Chihauhua and Sonora, thence crossing the Gila River and entering California on the southern border.
For a while he resided in Los Angeles, but in 1837 he obtained from the Mexican Government a grant of land at the foot of Mount Diablo, now the center of Contra Costa County. Here he made his permanent home.
Second among the American trail-blazers of Contra Costa County was Elam Brown. He had a varied and adventurous life, no small portion of which was spent in Contra Costa County, in whose affairs he played an important part.
He was born in Herkimer County, New York in 1797. The hardy traits of the pioneer were his birthright. As a child 12 months old he experienced his first migration when his parents moved to Berkshire, Massachusetts. When he was 7 they came west to Ohio, where they braved numerous hardships in true pioneer style.
In 1818, at the age of 21, he set out on foot for the French trading post of St. Louis, Missouri, 500 miles away. During the following winter he rafted unsuccessfully on the Missouri River. Then he went to Illinois, where he farmed on shares for the next 3 years, during which time he married the daughter of Thomas Allen.
His next venture was in moving west to what was known as the Platte Purchase, a tract of land bordering on the Missouri River, acquired by the Government from the Indians in 1836. There he cleared 180 acres of land, on which he resided for 10 years. It was there that his first wife died. He then determined to emigrate to the Pacific Coast, and in 1846 he headed a company and started on the long journey westward across the plains. The stout-hearted little band entered California in October of 1846, and toward the end of the same month they arrived at the present site of Sacramento, continuing thence to Santa Clara where most of the party settled.
About 1848, after fighting in Central California under General John C. Fremont, Brown learned that William A. Leidesdorff, a San Francisco trader, had a ranch for sale. This was the Rancho Alcalanes, where the present town of Lafayette is situated. This ranch was stocked with 300 head of cattle. This tract became the permanent home of Elam Brown in Contra Costa County. He soon became enthusiastic over its possibilities. He was especially pleased with the mild California winters.