What was the highest rank of soldier in world war 1?

Here are a few. Lt Col Paddy Blair Mayne The highest decorated solider was William Kingston of the 3rd brigade. The most decorated British Royal Marine was Scotland's Corporal Tom Hunter. Major William Martin, RM (fake identity) - The British disguised a body as a Royal Marine courier and gave him fake papers identifying him as Major Martin and dropped him off the coast of Spain. This was a British special operation to deceive the Germans from knowing that the Allies next amphibious landing would be at Sicily. This story was told in a book and movie "The Man Who Never Was".