The 1854 Gazetteer of the United States by Thomas Baldwin shows:

SONOMA, a county towards the N. W. part of California, has an area estimated at about 1200 square miles. It is bounded partly on the S. W. by the Pacific, intersected by the Russian river, and is drained by several small streams flowing into San Pablo bay, which lies on its S. border. The surface is uneven, having a mountain range passing nearly through the centre. The soil is fertile, especially along the streams, and in the southern portions well cultivated. Barley, wheat, potatoes, hay, onions, cattle, horses, and poultry are the staples. In 1852 it produced 87,851 bushels of barley; 23,108 of wheat; 278,542 of potatoes; 1266 tons of hay, and 491,671 pounds of onions. There were 4335 beef cattle; 3120 cows; 4400 horses, and 11,050 poultry. It contained 5 threshing machines, 6 blacksmith shops, and 1 tannery. Capital, Sonoma. Population, 2337.