Explain the Battle of San Juan Hill.

A decisive 1898 military action during the Spanish-American War became known as the Battle of San Juan Hill. It was called, at the time, the Battle for San Juan Heights, and it was on the nearby Kettle Hill that Theodore Roosevelt led his famed Rough Riders’ charge. These actions in and around Santiago, on the southern Cuban coast, were crucial to supporting the US military challenge to the Spanish forces.
A major port filled with Spanish ships, Santiago was strategically important to any hopes of US victory. The port was being protected by Spanish troops occupying fortifications strategically ranged along the high elevations overlooking Santiago. The US victory changed the course of the war and re-oriented the career of Theodore Roosevelt.
The assault on the hills took place on July 1, 1898. San Juan Hill had the highest elevation in the area. Aided by machine gun fire that preceded the troops’ charge, the combined army regulars and volunteers of the US Expeditionary Force charged up both hills. Despite numerous casualties and injuries, the Americans defeated the Spaniards. Each side lost about 200 men, but the American wounded numbered about 1,100, compared to fewer than 400 for the Spanish. Because of the defeat on the ground, Cuba’s Spanish governor ordered the fleet to put out to sea. Two days later, American naval forces destroyed it.
This battle turned the tide in the war. On July 17, 1898, the Spanish surrendered Santiago to the United States. In less than a month, the fighting was over in both Cuba and Puerto Rico. Following an armistice signed on August 12, the formal Treaty of Paris, of December 10, officially ended the war. In addition to relinquishing Cuba as a protectorate, Spain ceded Puerto Rico and Guam and sold the Philippines to the United States.
The famed Rough Riders were the 1st Volunteer Cavalry, a unit of the 1st Cavalry, led by Theodore Roosevelt. Roosevelt had been serving as Assistant Secretary of the Navy, but he resigned when war was declared. Obtaining his commission, he personally formed the 1st Volunteer Cavalry, drawing from Arizona, New Mexico, Oklahoma, and Indian Territory. The nickname was a play on the rodeo cowboys of the Buffalo Bill Wild West show.
The battle is important as well for the events it precipitated. For his “extraordinary bravery,” Lieutenant Colonel Theodore Roosevelt, Jr., was later awarded the US Medal of Honor. After the battle made him a household name, his entry into politics seemed natural, but no one could have predicted his rapid rise and the role that tragedy would play. In November 1898, Roosevelt was elected Governor of New York. The following year, he published his book, The Rough Riders, and in 1900, running on the winning ticket with William McKinley, he was elected Vice President. Less than a year later came McKinley’s assassination, and Roosevelt became President.
One of the most significant aspects about the military forces’ composition was controversial in its time. Significant numbers of African American soldiers, known at the Buffalo Soldiers, fought in Cuba. As the United States had prepared for, African Americans were divided about military service, in part because blacks could not be officers. Several all-black cavalry units fought in the San Juan Hill battle. Afterward, Roosevelt first praised the courage of the all-black 9th Cavalry as matching his Rough Riders—but later, he attributed the credit to their white officers.
https://www.encyclopedia.com/places/latin-america-and-caribbean/cuban-political-geography/san-juan-hill

https://www.nps.gov/prsf/learn/historyculture/buffalo-soldiers-and-the-spanish-american-war.htm