Henry Glass (1844–September 1, 1908) was a Rear Admiral in the United States Navy, best remembered for his role in the bloodless capture of Guam in the Spanish-American War. He was also a veteran of the American Civil War.
Glass was born in Kentucky and entered the United States Naval Academy in 1860. Though he was at the academy only two years, by 1863 he had been commissioned an ensign and participated in the bombardment of Fort Sumter. In 1865, he participated in the capture of Georgetown, South Carolina. After the war, in 1868, he was promoted to Lieutenant Commander. In 1874, he received his first command, the USS Jamestown. As commander of the USS Wachusett, Glass was the military commander in charge of Alaska in September 1881 and October 19, 1881 - March 12 1882. In 1894, he was promoted to Captain.
During the Spanish-American War, Glass was reassigned to the Pacific and commanded the cruiser USS Charleston. In the war he steamed to Guam and captured it for the United States. On arrival, he discovered the island to be nearly defenseless (with only a single cannon, in need of repair) and unaware of the war. Glass took the Spanish governor, Juan Marina, as a prisoner of war. He subsequently raised the American flag over the island before proceeding to Manila. During this period, Glass was effectively the first American Military Governor of Guam, though he only remained at the island for two days, from June 20 to 22nd, 1898. (The first real governor would be Richard Phillips Leary in 1899.)
In 1901, he was promoted to Rear Admiral.
The Glass Breakwater in Apra Harbor is named in his honor.
- "REAR ADMIRAL GLASS DEAD." New York Times. New York, N.Y.: Sep 3, 1908. pg. 7, 1 pgs
|- style="text-align: center;"
|width="30%" align="center" rowspan="1"|Preceded by
Final Spanish Governor |width="40%" style="text-align: center;" rowspan="1"|Commissioner of Guam
1898 |width="30%" align="center" rowspan="1"| Succeeded by
Francisco Portusach Martínez |- |}