By the mid-19th century the United States had become a nation of two distinct regions. The free states in New England, the Northeast, and the Midwest had a rapidly growing economy based on family farms, industry, mining, commerce, and transportation, with a large and rapidly growing urban population. Their growth was fed by a high birth rate and large numbers of European immigrants, especially from Ireland and Germany. The South was dominated by a settled plantation system based on slavery; there was some rapid growth taking place in the Southwest (e.g., Texas), based on high birth rates and high migration from the Southeast; there was also immigration by Europeans, but in much smaller number. The heavily rural South had few cities of any size, and little manufacturing except in border areas such as St. Louis and Baltimore. Slave owners controlled politics and the economy, although about 75% of white Southern families owned no slaves.