Which battle marked the first significant victory for the Union during the Civil War?

First Battle of Bull Run

The First Battle of Bull Run, also known as the Battle of Manassas, marked the first major land battle of the American Civil War. On July 21, 1861, Union and Confederate armies clashed near Manassas Junction, Virginia.

Explanation:

The battle at Fort Sumter

Explanation:

The battle at Fort Sumter took place on Apr 12, 1861 - Apr 13, 1861. It was the first battle of the civil war and a confederate victory.

explanation:

an oligopoly is a term used to clarify the structure of a particular market, industry, or organization. a market is considered oligopolistic or amazingly focused when it is shared between a few companies.