Mezue ahịrịokwu a: A mụrụ Granger na Zanesville, Ohio. Ọ gụsịrị akwụkwọ na United States Military Academy, na-etinye 28th na klas nke 1838. Granger ghọrọ onye isi ndị agha nke mbụ na 1839. O jere ozi dịka onye isi n'ụlọọrụ ndị uweojii.
Agha Seminole, ma bụrụ onye enyemaka onye nkuzi nke usoro na West Point na 1843/44. N'oge agha Mexico na America, e buliri Granger n'ọkwa onye isi na Septemba 8, 1847. Mgbe agha ahụ biri, e kenyere ya ọrụ n'ọtụtụ ebe n'ókèala Texas.