Ensign (flag)

An ensign is a maritime flag that is used for the national identification of a ship. It is the largest flag and is generally flown at the stern (rear) of the ship while in port. Depending on the ship's origin, it may sometimes be identical with a jack on the bow of the ship when in a port. Jacks are more common on warships than on merchant ships.

The Middle English ensign is derived from the Latin word insignia.

Vexillologists distinguish between three varieties of ensigns:

Some countries like the United States and France use just one flag as an ensign and also as a jack, while lacking special cantons and transparent identification. All ships of the seagoing services of the United States Government except for the United States Coast Guard fly the national flag as their ensign, although the ships of some agencies also fly an agency flag as a distinctive mark.

Countries like Ukraine, Italy, Russia, South Africa, Australia, New Zealand and Japan use different ensigns. These are strictly regulated and indicate if the vessel is a warship, a merchant ship, a ship under contract to carry mail, or a yacht, for example.

The national flags of several Commonwealth countries originated in the ensigns of the United Kingdom. Some of these national flags include those of Australia, New Zealand and several island nations. It is also very likely^{[citation needed]} that the Continental Union Flag, from which the flag of the United States developed, was strongly influenced by either the British Red Ensign or the flag of the British East India Company.

In nautical use, every boat uses a flag belonging to a specific Nation to indicate its organizational membership. This flag signifies the home port of the ship owner and that taxes for ship-related income are paid there. Flagging out always means that the relevant laws of the country apply on the ship. This includes employment contracts, safety regulations, stamp duty or value-added taxes.^{[citation needed]}

In most countries, especially in Europe and the countries of the Commonwealth of Nations, it is common for the ensign to display additional information, like whether it is a civil, state or military flag.^{[citation needed]}