Which industry did Andrew Carnegie dominate during the Gilded Age?

During the Gilded Age, Andrew Carnegie was a pivotal figure in the steel industry, transforming it into a major component of the American economy. He founded the Carnegie Steel Company, which became one of the largest and most profitable industrial enterprises in the world. Carnegie’s strategies included the adoption of innovative technologies and the implementation of vertical integration, where he controlled every aspect of the steel production process from raw materials to distribution. This not only improved efficiency but also significantly reduced costs, allowing his company to dominate the market. His success exemplified the era’s rapid industrialization and the rise of large-scale manufacturing in the United States.