did he participate in any war?
No
James B. Longacre
James Barton Longacre (August 11, 1794 – January 1, 1869) was an American portraitist and engraver, and the fourth Chief Engraver of the United States Mint from 1844 until his death. 
what is the gold dollar? A gold coin when was it first struck? 1849 and who issued this coin? United States Bureau of the Mint what is this coin made of? Gold who is the design of the coin attributed to? James B. Longacre where is he from? Delaware County, Pennsylvania
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James B. Longacre [SEP] Introduction
James Barton Longacre (August 11, 1794 – January 1, 1869) was an American portraitist and engraver, and the fourth Chief Engraver of the United States Mint from 1844 until his death. Longacre is best known for designing the Indian Head cent, which entered commerce in 1859, and for the designs of the Shield nickel, Flying Eagle cent and other coins of the mid-19th century. Longacre was born in Delaware County, Pennsylvania, in 1794. He ran away to Philadelphia at age 12, where he became an apprentice in a bookstore. His artistic talent developed and he was released to apprentice in an engraving firm.