The last living verified veteran

Veteran

A veteran is a person who has had long service or experience in a particular occupation or field; " A veteran of ..."...

 of World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 (28 July 1914 – 11 November 1918) is Florence Green

Florence Green

Florence Beatrice Green is the last known living veteran of the First World War. She was a member of the Women's Royal Air Force.-Biography:...

, a British woman

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

 who served in the Allied

Allies of World War I

The Entente Powers were the countries at war with the Central Powers during World War I. The members of the Triple Entente were the United Kingdom, France, and the Russian Empire; Italy entered the war on their side in 1915...

 armed forces. The last combat veteran was Claude Choules

Claude Choules

Claude Stanley Choules was the last World War I combat veteran, and was the last military witness to the scuttling of the German fleet in Scapa Flow. He was also the last veteran to have served in both world wars, and the last seaman from the First World War...

 who served in the British Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 (and later the Royal Australian Navy

Royal Australian Navy

The Royal Australian Navy is the naval branch of the Australian Defence Force. Following the Federation of Australia in 1901, the ships and resources of the separate colonial navies were integrated into a national force: the Commonwealth Naval Forces...

), and died 5 May 2011, aged 110. The last veteran who served in the trenches was Harry Patch

Harry Patch

Henry John "Harry" Patch , known in his latter years as "the Last Fighting Tommy", was a British supercentenarian, briefly the oldest man in Europe, and the last surviving soldier to have fought in the trenches of the First World War...

 who died on 25 July 2009, aged 111. The last Central Powers

Central Powers

The Central Powers were one of the two warring factions in World War I , composed of the German Empire, the Austro-Hungarian Empire, the Ottoman Empire, and the Kingdom of Bulgaria...

 veteran, Franz Künstler

Franz Künstler

Franz Künstler was, at age 107, the last known surviving veteran of the First World War who fought for the Austro-Hungarian Empire. Following the death of 110-year-old Ottoman veteran Yakup Satar on April 2, 2008, he was also the last Central Powers veteran of any nationality...

 of Austria-Hungary

Austria-Hungary

Austria-Hungary , more formally known as the Kingdoms and Lands Represented in the Imperial Council and the Lands of the Holy Hungarian Crown of Saint Stephen, was a constitutional monarchic union between the crowns of the Austrian Empire and the Kingdom of Hungary in...

, died on 27 May 2008 at the age of 107.

The total number of participating personnel is estimated by the Encyclopaedia Britannica at 65,038,810.