Marshal Ferdinand Jean Marie Foch (French pronunciation: ​[fɔʃ]) (2 October 1851 – 20 March 1929) was a French general and military theorist who served as the Supreme Allied Commander during the First World War. An aggressive, even reckless commander at the First Marne, Flanders, and Artois campaigns of 1914-1916, Foch became the Allied Commander-in-Chief in 1918 and successfully coordinated the French, British, American, and Italian efforts into a coherent whole, deftly handling his strategic reserves.

Foch was later acclaimed as "the most original military thinker of his generation". He became known for his critical analyses of the Franco-Prussian and Napoleonic campaigns and of their relevance to military operations in the new twentieth Century. His re-examination of France's defeat in 1870 was amongst the first of its kind. At the College, Foch was a professor of military history, strategy and general tactics while becoming the French theorist on offensive strategies.

When the Franco-Prussian War broke out in 1870, the 19 year-old Foch enlisted in the French 4th Infantry Regiment, which did not take part in combat. He remained in the army after the war. In 1871, he entered the École Polytechnique, choosing the school of artillery. In 1873, he received his commission as an artillery officer and served as a lieutenant in the 24th Artillery Regiment in Tarbes, despite not having had time to complete his course due to the shortage of junior officers. In 1876, he attended the cavalry school of Saumur to train as a mounted artillery officer. On 30 September 1878 he became a captain and arrived in Paris on 24 September 1879 as an assistant in the Central Personnel Service Depot of the artillery.

In 1885 Foch undertook a course at the Ecole Supérieur de Guerre where he was later an instructor from 1895 to 1901. He was promoted Lieutenant-Colonel in 1898, and colonel in 1903. As a colonel he became regimental commander of the 35th Artillery Regiment (35 R.A) at Vannes. An extremely short man, Foch was known for his physical strength and his sharp mind who always maintained a highly dignified bearing. Foch was a quiet man, known for saying little and when he did speak, it was a volley of words accompanied by much gesturing of his hands that required some knowledge of him to understand properly. One of Foch's favorite phrases was "Pas de protocole!" as Foch preferred to be approachable by all officers and whose only rigidity was always taking his meals at noon and at 7:30; otherwise Foch would work all sorts of irregular hours from dawn until well into the night.

During his time as an instructor Foch created renewed interest in French military history, inspired confidence in a new class of French officers, and brought about "the intellectual and moral regeneration of the French Army". His thinking on military doctrine was shaped by the Clausewitzian philosophy, then uncommon in France, that "the will to conquer is the first condition of victory." Collections of his lectures, which reintroduced the concept of the offensive to French military theory, were published in the volumes "Des Principes de la Guerre" ("On the Principles of War") in 1903, and "De la Conduite de la Guerre" ("On the Conduct of War") in 1904. While Foch advised "qualification and discernment" in military strategy and cautioned that "recklessness in attack could lead to prohibitive losses and ultimate failure," his concepts, distorted and misunderstood by contemporaries, became associated with the extreme offensive doctrines (l'offensive à outrance) of his successors. The cult of the offensive came to dominate military circles, and Foch's reputation was damaged when his books were cited in the development of the disastrous offensive that brought France close to ruin in August 1914.

English translation: Aeroplanes are interesting scientific toys, but they are of no military value.(1911)

In the euphoria of victory Foch was regularly compared to Napoleon and Julius Caesar. However, historians took a less sanguine view of Foch's talents as commander, particularly as the idea took root that his military doctrines had set the stage for the futile and costly offensives of 1914 in which French armies suffered devastating losses. Supporters and critics continue to debate Foch's strategy and instincts as a commander, as well as his exact contributions to the Marne "miracle": Foch's counter-attacks at the Marne generally failed, but his sector resisted determined German attacks while holding the pivot on which the neighbouring French and British forces depended in rolling back the German line.

In 1915, his responsibilities by now crystallised in command of the Northern Army Group, he conducted the Artois Offensive and, in 1916, the French effort at the Battle of the Somme. He was strongly criticised for his tactics and the heavy casualties that were suffered by the Allied armies during these battles, and in December 1916 was removed from command by Joffre and sent to command Allied units on the Italian front; Joffre was himself sacked days later.

A heavy cruiser and an aircraft carrier were named in his honor. An early district of Gdynia, Poland was also named "Foch" after the Marshal, but was renamed by the communist government after the Second World War. Nevertheless, one of the major avenues of the town of Bydgoszcz, located then in the Polish corridor, holds Foch's name as sign of gratitude for his campaigning for an independent Poland. Avenue Foch, a street in Paris, was named after him. Several other streets have been named in his honor in Melbourne, Ypres, Lyon, Kraków, Chrzanów, Grenoble, Quito, Beirut, New Orleans, Wynnum, Cambridge, Massachusetts, Mineola, New York, Queens, New York, Milltown, Shanghai (now part of Yan'a Road) and Singapore (Foch Road). A city quarter in the former French sector of Berlin is called Cité Foch in his honor. This is where French garrison Soldiers were housed while Berlin was divided. Fochville in South Africa was also named in his honour. A statue of Foch stands near Victoria railway station in London. He is the only Frenchman ever to be made an honorary field-marshal by the British. A statue of Foch stands on the Bapaume-Peronne road, near the village of Bouchavesnes, at the point where Messimy's chasseurs broke through on 12 September 1916. General Debeney spoke at the statue's unveiling in 1926, praising Foch's operational concepts of 1918. Foch also has a grape cultivar named after him. In the Belgian city of Leuven, one of the central squares was named after him after the First World War, but it was renamed in 2012. Mount Foch in Alberta is also named after him.

Late in 1917 Foch would have liked to have seen Haig replaced as C-in-C of the BEF by General Herbert Plumer; however, Haig would remain in command of the BEF for the remainder of the war.

Foch received the title of Doctor honoris causa of the Jagiellonian University of Kraków in 1918.

Foch was made a British Field Marshal in 1919, and, for his advice during the Polish–Bolshevik War of 1920, as well as his pressure on Germany during the Great Poland Uprising, he was awarded with the title of Marshal of Poland in 1923.

English Translation: To govern is to anticipate, we did: governing is waiting (1920)

On 1 November 1921 Foch was in Kansas City, Missouri, to take part in the groundbreaking ceremony for the Liberty Memorial that was being constructed there. Also present that day were Lieutenant General Baron Jacques of Belgium, Admiral David Beatty of Great Britain, General Armando Diaz of Italy and General John J. Pershing of the United States. One of the main speakers was Vice President Calvin Coolidge of the United States. In 1935 bas-reliefs of Foch, Jacques, Diaz and Pershing by Sculptor Walker Hancock were added to the memorial.

Foch died on 20 March 1929, and was interred in Les Invalides, next to Napoleon and other famous French Soldiers and officers.

A statue of Foch was set up at the Compiègne Armistice site when the area was converted into a national memorial. This statue was the one item left undisturbed by the Germans following their defeat of France in June 1940. Following the signing of France's surrender on 21 June, the Germans ravaged the area surrounding the railway car in which both the 1918 and 1940 surrenders had taken place. The statue was left standing, to view nothing but a wasteland. The Armistice site was restored by German prisoner-of-war labour following the Second World War, with its memorials and monuments either restored or reassembled.

On the outbreak of World War I, Foch was in command of XX Corps, part of the Second Army of General de Castelnau. On 14 August the Corps advanced towards the Sarrebourg–Morhange line, taking heavy casualties in the Battle of the Frontiers. The defeat of the XV Corps to its right forced Foch into retreat. Foch acquitted himself well, covering the withdrawal to Nancy and the Charmes Gap before launching a counter-attack that prevented the Germans from crossing the River Meurthe.

Ferdinand Foch was born at Tarbes in the Hautes-Pyrénées region. His Germanic first name reflects the ancestry of his father, a civil servant from Comminges whose lineage traces to the Alsace region in the 18th century. He attended school at Tarbes, Rodez and the Jesuit College at Saint-Étienne. His brother became a Jesuit priest, which may have hindered Foch's rise in the French Army since the Republican government of France was anti-clerical.