Philip Brown was born in Smithfield, New York on October 8, 1823. He graduated from Madison Univerisity in 1855, going on to become the principal of the Academy of the University until 1862.
He became the colonel of the 157th New York Infantry Regiment, which mustered in on September 19, 1862. He commanded it during most of its thee year service, including the Battle of Gettysburg, where it lost 307 casualties and he was wounded.
At the end of the war he became the colonel of the 7th United States Veteran Volunteers. He was brevetted Brigadier General of U.S. Volunteers on March 13, 1865, for gallant and meritorious services.
Brown left the army in 1866, operating a bakery business in St. Louis, Missouri. He died there on April 9, 1881 and is buried in Madison Street Cemetery in Hamilton, New York.