Iowa, midwestern state in the north-central United States; bordered by Minnesota in the north, Wisconsin and Illinois in the east, Missouri in the south, and Nebraska and South Dakota in the west.
Land and climate
Iowa is gently rolling plain, sloping toward the southeast. Great glaciers covered Iowa during the Ice Age, leveling hills and filling valleys with rich soil. In the southern portion of the state is a region of rich, wind-deposited soil and low hills and ridges cut by rivers. Northeast Iowa escaped most of the glaciers, and vertical cliffs rise as high as 400 ft from the river banks. Two of the nation's great rivers form part of Iowa's borders—the Mississippi, which forms the state's entire eastern boundary, and the Missouri, comprising most of the western border. All of Iowa's rivers drain into this great river system. The tributaries of the Mississippi—the Des Moines, Skunk, Iowa, Maquoketa, and Sapsipinicon rivers—drain in the eastern two-thirds of the state. The Missouri's principal tributaries include the Big Sioux, Little Sioux, Nishnabotna, Boyer, and Floyd rivers. Iowa has many small lakes and ponds concentrated in the north and northwest. Iowa's soil is probably the richest in the nation—85% to 90% of the state's area is suitable for cultivation, and about one-fourth of all the finest U.S. agricultural land is found in Iowa. The state has a continental climate, marked by cold winters and hot summers. Principal cities are Des Moines, Cedar Rapids, and Davenport.
Iowa is a leading agricultural state. Corn is Iowa's leading crop; Iowa produces about one-fifth of all corn grown in the United States. Other major crops are soybeans, oats, and hay. Iowans also raise large quantities of alfalfa, clover, sugarbeets, and wheat. Iowa raises more hogs than any other state, and ranks high in beef cattle, dairy cattle, and milk production. In manufacturing, food processing is Iowa's leading industry. Machinery production is second in importance. Iowa's chief mining product is limestone. It also produces gypsum, sand, and gravel.
Iowa's constitution was adopted in 1857. The governor serves a 4-year term. The state legislature, called the General Assembly, consists of 50 senators serving 4-year terms and 100 representatives serving 2-year terms. In the U.S. Congress, Iowa is represented by 2 senators and 6 representatives.
In prehistoric times, the area was home to Native Americans called the Mound Builders. When French explorers visited the region in 1673, it was home to Plains and Woodland tribes. By 1682, France had claimed the area. The territory west of the Mississippi was ceded to Spain (1762–1800), but in 1803 France sold it to the United States under the Louisiana Purchase. At first it remained Native American land, but by 1851 it had been opened to white settlers. The Territory of Iowa was created in 1838. In 1857, the state capital was established at Des Moines. World War II brought a growing demand for farm products, boosting Iowa's economy. New industries poured into the state from 1945 through the 1960s, but the 1980s brought hard times to farmers, including declining farm prices and land values. Its population has been dropping as young people leave to seek jobs elsewhere.