The development of the offshore petroleum industry is a remarkable story of inventiveness, entrepreneurship, hard work, and risk-taking that turned Louisiana's relatively isolated coastal communities into significant contributors to the U.S. and global economies. This industry emerged as local residents and returning World War II veterans applied skills, technologies, and can-do attitudes to overcome the many challenges of producing oil from below the ocean floor. Offshore workers initially came from Texas, Oklahoma, and Louisiana, but soon people from throughout the United States were attracted to the Gulf Coast. This industry, born in the Louisiana marshes, has grown to have a key place in the modern world. Yet, it is little known, understood, or documented, and its dynamic economic role is virtually invisible.