Dal served in the Imperial Russian Navy from 1814 to 1826, graduating from the Saint Petersburg Naval Cadet School in 1819. In 1826 he began studying medicine at Dorpat University; he participated as a military doctor in the Russo-Turkish War (1828–1829) and in the campaign against Poland in 1831–1832. Following disagreement with his superiors, he resigned from the Military Hospital in Saint Petersburg and took an administrative position with the Ministry of the Interior in Orenburg Governorate in 1833. He took part in General Perovsky's military expedition against Khiva of 1839-1840.