Philip Weaver Miller was born on March 1, 1843, in Pennsylvania to Levi and Catherine Miller. He probably grew up in Rush, Pennsylvania.
He served as a private in Company D of the 53rd Pennsylvania Militia Infantry from July 2, 1863, until August 20, 1863. He enlisted again on November 20, 1863, and he mustered in as a private in Company I of the 47th Pennsylvania Infantry. The regiment took part in the Shenandoah Valley campaign. In April 1865, he became a corporal in the 24th Veteran Reserve Corps.
He returned to Rush after the war, and he married Matilda Campbell. Their daughter Florence was born on September 23, 1866. He worked as a laborer, and by 1870, he owned $500 of personal property. He applied for a federal pension in February 1870 and eventually received one. By 1880, he was working as a farmer. His wife died in the late 1800s, and he married a woman named Isabel around 1893. By 1900, he was living in Catawissa, Pennsylvania, and working as a clerk in a bakery. He died there of a cardiac embolism on January 3, 1912.