In military organizations, the practice of carrying colours, standards, flags, or guidons, both to act as a rallying point for troops and to mark the location of the commander, is thought to have originated in Ancient Egypt some 5,000 years ago. The Roman Empire also made battle standards reading SPQR a part of their vast armies. It was formalized in the armies of Europe in the High Middle Ages, with standards being emblazoned with the commander's coat of arms.
Trooping the Colour is a ceremonial event performed every year on Horse Guards Parade in London, United Kingdom, by regiments of Household Division, to celebrate the official birthday of the British sovereign, though the event is not necessarily held on that day. It is also known as the Sovereign's Birthday Parade. Similar events are held in other countries of the Commonwealth. In the UK, it is, with the State Opening of Parliament, the biggest event of the ceremonial calendar, and watched by millions on TV and on the streets of London.
Historically, colours were once used on the battlefield as a rallying point. They display the battle honours of a regiment and are a focal point of Trooping the Colour. The ceremony has marked the sovereign's official birthday since 1748. Each year, one of the five Foot Guards regiments of the Household Division is selected to slowly troop (carry) its colour through the ranks of guards, who stand with arms presented. During the slow march-past, the colours are lowered before the monarch and during the quick march-past the colours fly. The monarch will salute the colours in return.
In military organizations, a colour guard (or color guard) is a detachment of soldiers assigned to the protection of regimental colours and the national flag. This duty is highly prestigious, and the military colour is generally carried by a young officer (ensign), while experienced non-commissioned officers (colour sergeants) are assigned to the protection of the national flag. These non-commissioned officers, accompanied in several countries by warrant officers, can be ceremonially armed with either sabres or rifles to protect the colour. Colour guards are generally dismounted, but there are also mounted colour guard formations as well.
The quarterdeck is a raised deck behind the main mast of a sailing ship. Traditionally it was where the captain commanded his vessel and where the ship's colours were kept. This led to its use as the main ceremonial and reception area on board, and the word is still used to refer to such an area on a ship or even in naval establishments on land. Many such facilities have areas decorated like shipboard quarterdecks.
In the 20th century the word came to be applied to the area at the stern of the ship, often (on naval vessels) used for secondary weapons and (on battleships) seaplane catapults.