Factory farming began taking shape in the 1920s with the rise of commercial chicken production, then expanded dramatically after World War II as cheap grain, new technology, and corporate consolidation transformed how America raised animals. There’s no single start date, but the period between 1920 and 1960 is when livestock production shifted from dispersed family farms to the concentrated, industrial model we recognize today.
An Accidental Start in 1923
The origin story of factory farming often traces back to a Sussex County, Delaware, farmer named Cecile Steele. In 1923, Steele ordered 50 chicks to raise for eggs but received 500 by mistake. Rather than send them back, she raised the extra birds for meat and turned a significant profit. That happy accident launched Delaware’s commercial broiler industry and demonstrated that chickens could be raised indoors, in large numbers, purely for meat rather than eggs.
Before Steele’s discovery, chicken was a luxury. Most farms kept small flocks for eggs, and meat chickens were a byproduct. Her success showed that raising birds at scale in confined spaces was not only possible but profitable, and other farmers in the Delmarva Peninsula quickly followed. Within a decade, the region had become the center of American poultry production.
World War II Changed Everything
The real acceleration happened during and after World War II. Wartime demand for cheap protein pushed the government to invest heavily in agricultural production. The USDA implemented price support programs, subsidies, and commodity allocation systems throughout the 1940s to keep food flowing to troops and allies. When the war ended, those policies didn’t simply vanish. Postwar price support and subsidy programs continued through the late 1940s, keeping grain prices artificially low and creating massive surpluses of corn and soybeans.
Cheap grain was the fuel that made factory farming economically viable. If you could buy feed for next to nothing, it made sense to confine thousands of animals in one place and push them to grow as fast as possible. The economics shifted from letting animals graze on pasture (which required land and time) to feeding them grain indoors (which required capital and infrastructure but produced meat faster and more predictably).
The Poultry Industry Led the Way
Poultry was the first sector to fully industrialize, and it did so with remarkable speed. Following WWII, the industry underwent rapid technological change: specialized breeding stock designed specifically for meat production, mechanized processing plants, and purpose-built growing houses that could hold thousands of birds. By 1955, production contracts between feed dealers and growers accounted for over 85 percent of broiler production. Independent chicken farmers were already becoming rare.
The key innovation wasn’t just bigger barns. It was vertical integration, a business model where a single company controls every stage of production. Feed dealers started financing chicks and feed for contract growers, then expanded into processing. Over the course of the 1950s, these companies consolidated breeding, hatching, growing, slaughtering, and packaging under one corporate roof. The farmer who raised the chickens often didn’t own them. The company did. The grower simply provided labor and a building, following the company’s specifications on feed, lighting, and temperature. This contract model, pioneered in poultry, became the template for how pork and eventually much of beef production would be organized.
Scale economies drove the consolidation. Specialized technology was expensive, so only larger operations could justify the investment. The result was fewer, bigger farms concentrated in regions of the South where land and labor were cheap.
Cattle Feedlots and the 1950s Grain Glut
Beef followed a different path but arrived at a similar destination. In 1930, Warren Monfort founded what would become Monfort Feedlots in Greeley, Colorado, pioneering the concept of the cattle feedlot. His idea was straightforward: instead of letting cattle graze on grass and arrive at slaughter at unpredictable weights and times, feed them a grain-based diet year-round in a confined area. This smoothed out the seasonal ups and downs of the cattle market and gave meatpackers a reliable, consistent supply.
The model didn’t fully take off until the postwar grain surplus made it cheap to feed thousands of cattle at once. By the 1970s, the Monfort feedlot in Greeley had become the largest in the world, feeding over 100,000 beef cattle in a single concentrated operation. That kind of scale would have been unimaginable on a traditional ranch. It required cheap corn, antibiotics to manage disease in crowded conditions, and a network of roads and refrigerated trucks to move the product to market.
How Factory Farms Are Defined Today
The U.S. government uses the term “concentrated animal feeding operation,” or CAFO, to classify these facilities by size. The EPA sets specific thresholds. A large CAFO holds at least 1,000 cattle, 2,500 pigs over 55 pounds, 125,000 broiler chickens (in dry manure systems), or 82,000 laying hens. Medium CAFOs fall below those numbers but still confine hundreds or thousands of animals and meet certain pollution criteria. Even a smaller operation can be designated a CAFO if regulators determine it’s a significant source of water pollution.
These aren’t obscure edge cases. Today, roughly 99 percent of livestock in the United States is raised in factory farm conditions. More than 98 percent of chickens, turkeys, pigs, and farmed fish come from these operations. Cattle are somewhat less concentrated, but about three-quarters still spend much of their lives in confined feeding operations. The system that Cecile Steele stumbled into in 1923 and that poultry companies refined in the 1950s now produces nearly all of the animal products Americans consume.
A Timeline of Key Turning Points
- 1923: Cecile Steele raises 500 broiler chickens for profit in Delaware, launching commercial meat chicken production.
- 1930: Warren Monfort founds the first major cattle feedlot operation in Greeley, Colorado.
- 1940s: Wartime price supports and grain subsidies create the economic foundation for cheap animal feed.
- Late 1940s: Postwar policies maintain grain surpluses and low feed prices, making confinement operations increasingly profitable.
- 1950s: Vertical integration transforms poultry. By 1955, over 85 percent of broilers are raised under contract rather than by independent farmers.
- 1960s–1970s: The feedlot model scales up for beef and begins expanding into pork. Monfort’s Colorado operation reaches 100,000 cattle.
Factory farming didn’t appear overnight. It was built across four decades through a combination of accident, war, government policy, and corporate strategy. Each step made meat cheaper and more abundant, while concentrating production into fewer, larger operations that look nothing like the farms most people picture when they think about where their food comes from.