Coontz graduated from the Naval Academy in 1885, and served at the Navy Department and in several ships over the next decade, among them vessels stationed in Alaskan waters and the Great Lakes.
He returned to the Navy Department late in 1894, to work on updating officer records, then was assigned to the cruiser USS Philadelphia, the Coast Survey and the cruiser USS Charleston.
During the Spanish–American War Charleston and Coontz seized control of Guam, then joined Admiral George Dewey's forces in the Philippines.
Coontz would remain in the Pacific, seeing action in the Philippine–American War.
Following further duty afloat and ashore, Coontz, then a lieutenant commander, was Executive Officer of the battleship USS Nebraska) during the 1907–1909 world cruise of the "Great White Fleet".

In 1899, Coontz became a Veteran Companion of the Pennsylvania Society of the Military Order of Foreign Wars.

After promotion to commander in 1909, Coontz was Commandant of Midshipmen at the Naval Academy.
In 1912–13, he was Governor of Guam.
Captain Coontz then served as Commanding Officer of the battleship USS Georgia), followed by duty as Commandant of the Puget Sound Navy Yard and the 13th Naval District.
He held those positions until late in 1918.
Following a brief period as acting Chief of Naval Operations, Rear Admiral Coontz assumed command of a battleship division in the Atlantic.

Coontz had just been assigned to the Pacific Fleet in September 1919, when he was selected to become Chief of Naval Operations (CNO), succeeding Admiral William S. Benson.
Reportedly, his term as CNO was marked by unceasing pressure for economy, Congressional unhappiness over base closings, diplomatic efforts to achieve naval limitations, internal Navy Department conflicts over organization and the best ways to manage new technologies, plus the naval fallout of the Teapot Dome scandal.
While dealing with these problems, Admiral Coontz established a unified United States Fleet and strengthened the CNO's position within the Navy Department.

Relieved as CNO in August 1923, by Admiral Edward W. Eberle, Coontz was able to return to sea as Commander in Chief of the United States Fleet.
In 1925, he led the fleet on a trans-Pacific visit to New Zealand and Australia, the first massed deployment of American battleships since the "Great White Fleet" cruise, nearly two decades earlier, and a valuable demonstration of their strategic reach.
Admiral Coontz is also acknowledged for his key role in the promotion of US naval aviation.
He lobbied for converting the USS Lexington and USS Saratoga from Lexington-class battlecruisers to Lexington-class aircraft carriers following the Washington Naval Treaty, ships that would prove vital for training in the inter-war years and as fighting ships during World War II.
From October 1925, until his retirement in June 1928, Coontz served as Commandant of the Fifth Naval District, reverting to the rank of rear admiral.
Coontz graduated from the Naval Academy in 1885, and served at the Navy Department and in several ships over the next decade, among them vessels stationed in Alaskan waters and the Great Lakes. He returned to the Navy Department late in 1894, to work on updating officer records, then was assigned to the cruiser USS Philadelphia, the Coast Survey and the cruiser USS Charleston. During the Spanish–American War Charleston and Coontz seized control of Guam, then joined Admiral George Dewey's forces in the Philippines. Coontz would remain in the Pacific, seeing action in the Philippine–American War. Following further duty afloat and ashore, Coontz, then a lieutenant commander, was Executive Officer of the battleship USS Nebraska) during the 1907–1909 world cruise of the "Great White Fleet".
In 1899, Coontz became a Veteran Companion of the Pennsylvania Society of the Military Order of Foreign Wars.
After promotion to commander in 1909, Coontz was Commandant of Midshipmen at the Naval Academy. In 1912–13, he was Governor of Guam. Captain Coontz then served as Commanding Officer of the battleship USS Georgia), followed by duty as Commandant of the Puget Sound Navy Yard and the 13th Naval District. He held those positions until late in 1918. Following a brief period as acting Chief of Naval Operations, Rear Admiral Coontz assumed command of a battleship division in the Atlantic.
Coontz had just been assigned to the Pacific Fleet in September 1919, when he was selected to become Chief of Naval Operations (CNO), succeeding Admiral William S. Benson. Reportedly, his term as CNO was marked by unceasing pressure for economy, Congressional unhappiness over base closings, diplomatic efforts to achieve naval limitations, internal Navy Department conflicts over organization and the best ways to manage new technologies, plus the naval fallout of the Teapot Dome scandal. While dealing with these problems, Admiral Coontz established a unified United States Fleet and strengthened the CNO's position within the Navy Department.
Relieved as CNO in August 1923, by Admiral Edward W. Eberle, Coontz was able to return to sea as Commander in Chief of the United States Fleet. In 1925, he led the fleet on a trans-Pacific visit to New Zealand and Australia, the first massed deployment of American battleships since the "Great White Fleet" cruise, nearly two decades earlier, and a valuable demonstration of their strategic reach. Admiral Coontz is also acknowledged for his key role in the promotion of US naval aviation. He lobbied for converting the USS Lexington and USS Saratoga from Lexington-class battlecruisers to Lexington-class aircraft carriers following the Washington Naval Treaty, ships that would prove vital for training in the inter-war years and as fighting ships during World War II. From October 1925, until his retirement in June 1928, Coontz served as Commandant of the Fifth Naval District, reverting to the rank of rear admiral.
Robert Coontz