Before the arrival of the Romans, Britain was home to a variety of cultures and societies, each with its own unique forms of political organization. These ranged from small, independent tribes to larger, more complex societies.

One of the most well-known groups in pre-Roman Britain were the Celts, who were spread across much of Western Europe. They were organized into loosely-connected tribes, each with their own chieftain or king who held power over a small area. These tribes were often in conflict with one another, and alliances were constantly shifting.

Another group in pre-Roman Britain were the Britons, who were descendants of the original inhabitants of the island. They too were organized into tribes, but their societies were more hierarchical than those of the Celts, with some tribes having kings who held power over a larger area.

In addition to these groups, there were also a number of smaller societies in pre-Roman Britain, such as the Iceni and the Trinovantes, who were organized into more complex political structures. The Iceni, for example, were led by a queen named Boudica, who was able to unite several tribes in a rebellion against the Romans in 60 AD.

Overall, the political organization of pre-Roman Britain was diverse and varied, with each group developing its own unique forms of governance and social structure.

The political structures of pre-Roman Britain varied among different tribes and societies, and there was no uniform system of government across the island. However, here are some examples of political structures and leadership titles of some of the tribes and societies:

The Celts: The Celts were organized into loosely connected tribes, each with their own chieftain or king who held power over a small area. The chieftain was often chosen for their bravery and military prowess, and they were responsible for leading their people in times of war and making important decisions for their tribe. There were also druids who held religious and legal authority within the Celtic society.

The Britons: The Britons were organized into larger tribes or confederacies, which were often headed by a king or queen. The title of the king or queen varied among different tribes, with some using the term "rex" and others using "pendragon" or "brenin". The king or queen had supreme authority over their tribe and was responsible for maintaining order and protecting their people.

The Iceni: The Iceni tribe, led by Queen Boudica, had a hierarchical political structure. The queen held the highest position of power and was supported by a council of nobles who advised her on important matters. The council was made up of the most influential members of the tribe, such as the warrior elite and the druids.

The Trinovantes: The Trinovantes tribe was another group that had a more complex political structure. They were organized into a confederacy of smaller tribes, with a council of chiefs that met to make decisions about matters affecting the confederacy as a whole. Each tribe had its own leader or chieftain, but they were subservient to the council of chiefs.

Overall, the leadership titles of pre-Roman Britain varied depending on the tribe or society. They ranged from chieftains, kings, queens, rex, pendragon, brenin, and council of chiefs.

Before the arrival of the Romans, the Britons and Celts did not have any large cities in the modern sense of the term. Their societies were largely based around small, rural settlements and villages, with a few larger settlements that served as political, religious, or economic centers.

One of the largest settlements in pre-Roman Britain was the hillfort at Maiden Castle in present-day Dorset. The fort was surrounded by multiple walls and ditches, and it may have been home to several hundred people. Other large hillforts include Danebury in Hampshire, Cadbury Castle in Somerset, and the Welsh hillfort of Pen Dinas.

There were also some larger towns and trading centers, such as Colchester, which was the capital of the Trinovantes tribe and an important center for the tin trade. Other towns included Verulamium (modern-day St Albans) and Camulodunum (modern-day Colchester).

However, it is important to note that these settlements were still relatively small by modern standards and were not as densely populated as large cities today. It was only after the Roman conquest of Britain that large, urban centers such as London, Bath, and York began to emerge.