Union Jack Flag - Official UK National Flag | Symbol of British Identity #1787193 (License: Personal Use)

The Union Jack is the de facto national flag of the United Kingdom, formed by superimposing the red cross of St George (England), the white saltire of St Andrew (Scotland), and the red saltire of St Patrick (Ireland) on a blue field. Its proportions are typically 1:2, and it has been in use since 1801 following the Act of Union with Ireland. The flag is flown across government buildings, at royal events, and during national celebrations like Trooping the Colour and Remembrance Day.

This image is commonly used on government websites, educational resources, travel guides, and news articles covering UK politics, history, or international relations; it serves users seeking visual identification, historical context, or symbolic representation of Britain.