Final answer:
Carnegie and Rockefeller rose to prominence in America's industrial age, with Carnegie dominating the steel industry and Rockefeller the oil industry through aggressive business practices. Both used innovation and new business models to transform the economy, while J. P. Morgan, born wealthy, shaped industry through strategic investments.
Step-by-step explanation:
Andrew Carnegie and John D. Rockefeller came into power during the industrial age at the end of the 19th century, leveraging the growth of big business through technical innovation and new business models.
Carnegie, rising from humble beginnings, became the world's leading steel producer, having introduced the Bessemer process in his Pittsburgh steel factory, promoting vertical integration and dominating the steel market. In contrast, Rockefeller built his vast fortune in the oil industry through aggressive and often predatory business practices.
Both men played crucial roles in transforming the American economy, with their business practices contributing to the standardization of social structures and helping to define the era of industry in America.
As for J. P. Morgan, he was distinct from Carnegie and Rockefeller in that he was born into wealth and fashioned his wealth through savvy investment banking. His company facilitated the expansion of businesses such as Carnegie's and Rockefeller's through strategic investments, which also gave Morgan significant influence over their operations.
Their collective influence reshaped the landscape of American industry and social structure, transitioning power from the aristocracy to industrious entrepreneurs who implemented models of management such as horizontal and vertical integration, trusts, and holding companies.