D.
All of these were problems the Roman Empire was facing in the late second and third centuries.
The <em>Robber Barons</em> were millionaire entrepreneurs and owners of half of the Unites States in the last third of the 19th century. These men were the influencers of all the politicians of that time because they extorted the main ones in power; as we know, the money controls the world, commonly nobody can resist to the money.
Some historians consider the <em>Robber Barons</em> as boosters of the United States economy, before their apparition the country were an agricultural country and thanks they it becomes as an industry.
Finally, we will mention the most named <em>Robber Barons</em> and their principles contributions to the country:
- John D. Rockefeller, First oil monopoly.
- Andrew Carnegie, Cranegie Steel Company.
- Cornelius Vanderbilt, Grand Central Depot.
- J.P. Morgan, General Electric, bought Carnegie's company and founded the U.S. Steel.
- Leland Stanford, Stanford University.
Boston African American National Historic Site, Fort Sumter and Fort Moultrie National Historical Park. The 54th Massachusetts Volunteer Infantry Regiment is best known for its service leading the failed Union assault on Battery Wagner, a Confederate earthwork fortification on Morris Island, on July 18, 1863.
