Great Britain is a monarchy.
The United Kingdom, which includes Great Britain, is a constitutional monarchy. This means that while there is a monarch (currently King Charles III), their powers are largely ceremonial and symbolic. The real political power rests with elected officials in Parliament. The monarchy has a long history in Britain, and although its role has changed over the years, it remains an essential aspect of British culture and identity.
In a republic, the head of state is usually elected and represents the interests of the citizens. However, in the UK, the monarch’s role is defined by historical traditions and constitutional laws, which means that the people do not elect the monarch. Instead, the position is inherited. This system is quite different from a republic, where leaders are typically chosen through electoral processes.