Phillip was born in 1897, at Penallt, son of George and Mary Ann Roberts Penallt. The 1901 census shows he resided at Old House Farm, Penallt, aged 4. The 1911 census shows he was living at Cherry Tree Cottage, Tregagle.
By December 29th 1916, he is listed as having joined The Welsh Horse Regiment. He enlisted in Newport town. At that time it was stated that he resided in Cwmcarvan.
He became 11710 Private Phillip Harry Roberts and later was transferred to 2nd Battalion, then to 17th Battalion Royal Welsh Fusiliers, becoming 55541 Private Phillip Harry Roberts. The 1918 Register of Absent Voters showed him residing at Cherry Tree Cottage.
Phillip died 23rd November 1918, aged 21, of wounds or disease after the signing of the Armistice. He served in France and Flanders. His medal entitlement was British War Medal and Victory Medal but not the 1915 Star. He is buried at The St Sever Cemetery Extension Rouen.