Indianapolis is the capital of the U.S. state of Indiana, and the county seat of Marion County, Indiana. It is Indiana's largest city and is the 14th largest city in the U.S., the third largest city in the Midwest (behind Chicago and Detroit), the second most populous state capital (after Phoenix, Arizona), and the most populous state capital east of the Mississippi River. For much of its history, Indianapolis has oriented itself around government and industry, particularly manufacturing. Today, Indianapolis has a much more diversified economy, contributing to the fields of education, health care, and finance. Tourism is also a vital part of the economy of Indianapolis, and the city plays host to numerous conventions and sporting events.