Dee ihe ọzọ maka paragraf a - A mụrụ Duncan ma zụlite ya n'ime ime obodo Chanceford Township na ndịda ọwụwa anyanwụ nke York County, Pennsylvania, nke dị n'akụkụ Osimiri Susquehanna sara mbara. A họpụtara ya na United States Military Academy na July 1, 1845, ma gụsịrị akwụkwọ na West Point na June 1849. Ọ bụ ezigbo nwa akwụkwọ, ọ nọ n'ọkwa nke ise n'ime ụmụakwụkwọ iri anọ na atọ. N'ihi ọkwa agụmakwụkwọ ya dị elu, e mere ya onye isi nke abụọ ma kenye ya na Second US Artillery na July nke afọ ahụ. N'oge na-adịghị anya mgbe nke ahụ gasịrị, na Ọktoba 31, e nyere ya ọkwa nke onye isi nke abụọ ma kenye ya ọrụ na Third Artillery. Ọ hụrụ ọgụ mbụ ya na-eje ozi n'ọgụ ndị Florida
megide ndị India Seminole.