Friedrich Sigmund von Waldow was royal Prussian Major General, Chief of the Cuirassier Regiment no 8 and hereditary lord of Mehrenthin.
He fought from 1700 for Sweden under Charles XII and participated in the Great Northern War, as well as at the Battle of Poltava.
On 15 November 1715 he moved to become a lieutenant colonel in the Prussian Army, probably campaigning with his older brother.
On 16 July 1724 he became a colonel and at the 1 December 1724 and Waldow was transferred on 26 February 1728 as a commander in the Cuirassiers No.
His first wife was in 1715 Hedwig Katharina von Oppen (18 February 1694 – 28 April 1725); they had several children, including: His second marriage in 1715 was to Helene of Guntersberge (died 6 August 1733) and they had the following children: In 1738 he married Luise Magdalene von Bornstedt (died 18 April 1764).