Since when has the rank of James Cassels been at its current level in the British Army?
Field marshal (United Kingdom) Field Marshal has been the highest rank in the British Army since 1736. A five-star rank with NATO code OF-10, it is equivalent to an Admiral of the Fleet in the Royal Navy or a Marshal of the Royal Air Force in the Royal Air Force (RAF). A Field Marshal's insignia consists of two crossed batons surrounded by yellow leaves below St Edward's Crown. Like Marshals of the RAF and Admirals of the Fleet, Field Marshals traditionally remain officers for life, though on half-pay when not in an appointment. The rank has been used sporadically throughout its history and was vacant during parts of the 18th and 19th centuries (when all former holders of the rank were deceased). After the Second World War, it became standard practice to appoint the Chief of the Imperial General Staff (later renamed Chief of the General Staff) to the rank on his last day in the post. Army officers occupying the post of Chief of the Defence Staff, the professional head of all the British Armed Forces, were usually promoted to the rank upon their appointment.
Nick Carter (British Army officer) General Sir Nicholas Patrick "Nick" Carter, {'1': ", '2': ", '3': ", '4': "} (born 11 February 1959) is a senior British Army officer. He served as commanding officer of 2nd Battalion, Royal Green Jackets in which role he was deployed to Bosnia in 1998 and Kosovo in 1999. After service in Afghanistan, he took command of 20th Armoured Brigade in 2004 and commanded British forces in Basra. He was subsequently appointed General Officer Commanding 6th Division, which was deployed to Afghanistan with Carter as Commander ISAF Regional Command South, before he became Director-General Land Warfare. After that he became Deputy Commander Land Forces in which role he was the main architect of the Army 2020 concept. After a tour as Deputy Commander, International Security Assistance Force, he assumed the position of Commander Land Forces in November 2013. In September 2014, he became head of the British Army as Chief of the General Staff succeeding General Sir Peter Wall.