Julius August Reinhold von Grawert was born on 28 December 1746 in Königsberg, East Prussia. He was the son of Johann Benjamin von Grawert (1709–1759) and his wife Christiane Sophie von Grawert (née von Schollenstern) (1717–1796). Young von Grawert entered military service in 1759, during the Third Silesian War, when he enlisted for 12 years and right in time for the Battle of Kunersdorf. After the Peace of Hubertusburg, he was commissioned as a Premier-Leutnant in the Infantry Regiment "von Tauenzien" in Breslau.