Context : His uncle, also Charles Rainsford (died 1778), was deputy lieutenant of the Tower of London and used his influence to get him made second cornet in General Bland's 3rd dragoons in March 1744, a unit at that time active in the Flanders theatre of the War of the Austrian Succession. 
Subject : Charles Rainsford 
Relation : military branch
With which military branch did Charles Rainsford serve with?