Background
Pierre Ronarc'h was born on 22 November 1865 in Quimper.
Pierre Ronarc'h was born on 22 November 1865 in Quimper.
He entered the Naval Training College at the age of fifteen and saw his first action as an ensign in the Comoro Islands off Madagascar.
In 1900, in a preview of his World War I exploits, Ronarc'h led an artillery unit in the expedition that lifted the siege of the foreign legations at Peking. Two years later Ronarc'h was advanced to the rank of commander, the youngest officer in the French navy to hold that grade. The Russo-Japanese War aroused Ronarc'h's interest in naval mines, and his superiors encouraged him to become France's leading authority on the subject. He invented a mine-sweeping device that played a significant role in the First World War. Promoted captain in 1908, Ronarc'h commanded a crack combined force of destroyers, submarines, and torpedo boats under Admiral Boue de Lapeyrere, France's naval commander in the Mediterranean. In the first months of 1914 he was promoted rear admiral.
Ronarc'h's service in the First World War began in the trenches. With a force of 6,000 sailors and marines he helped defend Paris during the battle of the Marne, then entered the northern sector of the western front in mid-October. His two naval regiments helped cover the Belgian army's retreat from Antwerp, then clung to the important Dixmuiden bridgehead on the Yser in savage, house-to-house fighting. When relieved in mid-November, his shattered force had lost nearly all of its original members in helping to deny the Germans possession of the Channel ports.
The submarine threat claimed Ronarc'h's attention next. Promoted vice admiral, he became director of the French antisubmarine effort in November 1915. Ronarc'h drew armed trawlers into service for antisubmarine patrols and shifted torpedo boats and destroyers from the Channel to the Mediterranean, where German and Austrian U-boats were taking a heavy toll of Allied shipping. In cooperation with the British, the Mediterranean was divided into separate zones where each navy could take primary responsibility for protecting passing merchant vessels.
In May 1916, Ronarc'h took charge of the newly formed Naval Zone of the Northern Armies, a stretch of water extending from Nieuport to the outskirts of Le Havre. After having reinforced the Mediterranean at the expense of this region, he had the ironic task of defending the French side of the Channel with only a fraction of his country's naval resources.
Ronarc'h's zone was the scene of numerous small actions. He skillfully deployed his thin force of submarines, destroyers, patrol boats, and aerial units to shield merchant shipping and to prevent enemy raids on the armed trawlers that helped guard the antisubmarine nets. Ronarc'h found much of his work involved close cooperation with the British commanders of the more powerful Dover Patrol. The relationship was a cordial one, but the task of blocking U-boats from passing the Dover Straits lay beyond the combined French and British forces until well into 1918. Ronarc'h provided both advice and combat vessels to support the British raid on Zeebrugge in April 1918. In May Ronarc'h argued successfully against the call of General Haig to abandon Dunkirk in the face of the German spring offensive in Flanders. To the admiral, such a withdrawal meant the inevitable loss of Calais and the cross-Channel shipping lanes.
On October 17 along with Admiral Keyes of the Dover Patrol, Ronarc'h accompanied the Belgian royal family on their solemn seaborne return to Ostend. The months following the armistice found him sweeping his northern zone clear of mines. He served briefly as chief of France's Naval General Staff, then retired in 1920. Ronarc'h died in Paris, April 1, 1940.
As Thomazi has pointed out, Ronarc'h's role in the years 1916-1918 was unspectacular but essential. Only by assuring the passage of millions of men and thousands of transports across the Channel with miniscule losses were the Allies able to continue the war. The capable French admiral with his extensive experience in fighting the U-boat might well have played a still larger role in the entire war. Ronarc'h was perhaps a superior choice for the large Mediterranean theater, with its international complexities and its continuing war against the submarines, than the succession of Dartige du Fournet and Gauchet, the diplomatically unsophisticated battleship admirals who found themselves misplaced on the center stage of France's naval war.