It is a common question, and different nations all have different opinions on their contribution and importance to winning the war. However the war was more like a continental siege on an industrial scale rather than the blitzkrieg and heroics we see in movies. This makes the role of the Royal Navy and French Armies important in the containment and blockading of Germany to the point where it was unable to compete on the battlefield; economically, socially or politically.

Prior to World War I there was a level of globalisation and trade that wasn't seen again until the 1990s. World War I, the depression and consequent protectionist and nationalist policies stopped that globalisation but in 1914 national wealth was highly dependent on the inter-connectedness of trade and communications. Crippling Germany's ability to make war would require cutting them off from the rest of the world's trade, technology and resources. This was the role for the British Royal Navy. Niall Ferguson writes;

Significantly, the first Royal Navy action of the war - on August 5th, the day after Britain's entry - was the severing of all Germany's international telegraph cables, which ran along the ocean floor to France, Spain, North Africa and the United States.

Britain did not lose global blue water supremacy to the United States until World War II, consequently in WWI it was in the ideal geographical location and force structure to conduct a naval blockade of Germany.

The second important component of a continental blockade was sufficient forces to lay siege to Germany and the territory it occupied. This was made easier by industrial warfare which proved advantageous to defence. Technology, weaponry and

tactics had to advance before industrial warfare could be used offensively with any success. Byng and Monash by war's end were coordinating ground, armoured and aerial forces in a very modern manner. Arguably, offensive industrial warfare did not come of age until the German blitzkrieg's of WWII where air-power was used as mobile forward artillery.

The majority of forces on the western front were supplied by the French Army. British forces, including Australian, only operated on a small part of the front in Belgium and northern France whereas French forces held a majority of the line from northern France to the Swiss border.

Source: Wikipedia

Russia and France suffered the greatest number of military deaths, though industrial warfare brought massive casualty rates for every nation involved, but Russia collapsed militarily and socially under the pressure of such dehumanising warfare. France suffered similar problems with whole Division falling into mutiny, but managed to hold it the army and front line together without suffering revolution as Russia did.

Russia's exit from the war did not help Germany much either as Russia fell into revolutionary chaos which limited access to trade and resources, but it would not have mattered. The globalised trading world that existed before the war was shattered by 1917 and would take seventy years to resurrect itself again.

In World War I the high-tech industries of the day were aviation and submarines. These required cutting edge science, engineering, design and materials. Germany still produced amazing designs, but in the area of materials and production it had fallen behind by late 1916. A good example is the deployment of 180hp and 200hp SE5as and Spads to the front with the Hispano Suiza engine. This was the last time that Germany would be able to match the Allies for horsepower in deployed squadrons.

In the last days of the war the United States was spitting out 400hp engines while the best Germany could come up with was the 110hp rotary. Some of the the Fokker DVIIs had the high-performance 185hp BMW engine, but they were in small numbers at war's end. In comparison the British were rolling out the 230hp Sopwith Snipe which was the least powerful of the next-gen 1918 aircraft.

It is probably a fair statement that the blockade affected Germany's ability to deploy high-technology production in numbers by 1916. It would take another two years, and defeat in the Battle of the Marne in early 1918 for Germany to be unable to continue in a state of warfare socially, economically or politically.