The number of castles varied greatly depending on what part of Europe, and what time frame within the Medieval period you are looking at.

However, castles were very common. There were thousands and thousands of castles built in Medieval Europe.

Let's look at my favorite castles, the small castles which protect every village in the South of France. In particular, let us look at the small castles in the region of the Uzege, around the town of Uzes in Gard, in the South of France.

There are about 30 villages within a 20km radius of Uzes. All 30 have a small castle. Most were built in the 12th century (though many were continuously modified into later centuries, and a few were built later). The average population of these villages was perhaps 400 people in Medieval times.

The city of Uzes itself was a walled city and has a larger castle (now called the “Duche”, as it belongs to the Dukes of Uzes (the premier, or oldest, Duchy in the French peerage) – who’s predecessors were not Dukes in the 12 Century). The Duche was built on the remains of a Roman “Castrum” or camp, which became the seat of the governors of the area in the first millennium.

In the city of Uzes there are also two other great medieval towers or keeps, one owned by the bishops of Uzes, and one owned (eventually) by the Kings of France. These three fortresses kept a balance of power between King, Church and Nobles in the city of Uzes.

We will not concentrate on these larger castles. (There were even grander and more powerful castles built nearby in Medieval times, such as the great castles at Tarascon and Beaucaire where the powers of the Kingdom of France and the Holy Roman Empire were embodied in stone, defying each other across the river Rhone. The church also built great fortifications to protect the Papacy in Avignon, such as the “Palais du Papes”, and “Chateau Neuf du Pape”.)

These grand castles were mostly built later than the 12th century. There are not so many of them (but still, quite a few in a fairly small area.)

The vast majority of the castles in this restricted area were the small village castles, each housing a “seigneur” or knight and his family and servants, which protected the small villages of the Uzege.

It was the 12th century. Times were lawless and dangerous. Raiders were prevalent, especially Saracens, landing on the coast from North Africa or Spain and raiding inland to seize treasure and particularly slaves. Sometime in the 12th century, raiders became prevalent and strong enough, and local armies weak enough that almost every village began to fortify.

Isolated farms were abandoned. The population concentrated in hilltop or ridge top villages tightly packed, made of stone, and somewhat defensible. They either had a wall, or the outer walls of the houses made a wall with only a few streets which could be blocked leading into the village. The only farms left in the valley bottoms and the rich farmlands were large farms called “mas” which means “big”, which were stone built and defensible themselves.

It was quite a sacrifice to live in villages in a more defensible location, because it meant long walks every morning and evening to get to the fields, but the times were dangerous enough that the sacrifice was made. In fact, these defensible villages didn’t provide enough protection. Every village began to build a castle, and support a knight who could be armed and armored for war and protect the village.

The more unsettled and dangerous the times in an area, the more castles were built to provide protection and defense.