Peter was born in Airdrie, Scotland, on the 17th of February 1858, and he enlisted in the US Marine Corps in 1883. While I was unable to find details of his emigration to the United States, his early life, or even his later life, I do know that he was part of a group of Navy Bluejackets and Marines that deployed to China in support of the Boxer Rebellion and his actions against militants, snipers, and Chinese cavalry, earned him the Medal of Honor. The citation reads:

In action with the relief expedition of the Allied forces in China during the battles of 13, 20, 21, and 22 June 1900. Throughout this period and in the presence of the enemy, Stewart distinguished himself by meritorious conduct.

Peter received the Medal of Honor on the 19th of July 1901 and I was unable to find any record of marriage or children. Fourteen years after his actions in China, Peter Stewart died on the 17th of June 1914, at the age of 55. He is buried in the Cypress Hills National Cemetery in Brooklyn, New York: Section 2, Grave 7303.