How did the medieval titles of nobility develop?

Originally, the titles of monarchs were emperor or king.

There was the title of duke, which was applied to a powerful warlord governing a large territory.

There were princes, and some of these were not sons of kings, but the term was never clearly defined, except as applied to the son of a king.

There were counts. The term originally meant companion of the monarch, but came to mean a military leader for a district, or, in some places, it was just a military rank below general.

These were the ranks at the beginning of the Middle Ages. Development after that varied a bit from place to place, but was overall rather uniform.

Taking England as an example, the person at the top of the feudal pyramid was always a king. But sometimes there were lesser kings below the chief king. These lesser kings, who we might call viceroys, were not uncommon among the Anglo-Saxons. This same thing was occasionally done later; for example, Prince Henry, the son of King Henry II of England, was crowned King of England before his father died, and without his father stepping down. Since the young King Henry died before his father, he usually does not appear in lists of English kings.

The Anglo-Saxons had earls (equivalent of counts), but did not seem to have much in the way of knights. Their army at Hastings was entirely composed of infantry.

The rank of yeoman existed among them, though not by that name, and was for a man who was a small landholder who would also be a soldier. The yeoman was above a freeman in rank, who was, in turn, above a serf. Not considered members of the nobility of the time, land owners could be by later standards, when the term nobility came to include landed gentry of rank below knights.

When the Normans invaded, their most important soldiers were knights. William the Conqueror retained the title of earl for the people who were given counties to govern, and always had a large number of knights to fight the rebellions that arose. He also introduced the new title of baron, which indicated a hereditary governor of a territory smaller than a county.

So the feudal pyramid under William looked like this:King

Earl

Baron

Knight

yeoman

tenant farmer or freeman

serf

slave

Later, in 1301, Edward I made his son Prince of Wales, formalizing that title as having meaning beyond simply meaning son of a king. Starting in 1328, the hereditary title of baronet was created for people below the rank of baron, but not necessarily knights, whose rank was never hereditary in England. In 1337, dukes were created, ostensibly as powerful military leaders above the rank of Earl. (The rank of marquess was created after the Middle Ages for people of rank between duke and earl.) In 1440, the rank of viscount was created, indicating a person between the ranks of earl and baron. Meantime, slaves had long since disappeared, and serfs were pretty much gone as well, so the class structure looked like this (ignoring the middle class): King

Prince

Duke

Earl

Viscount

Baron

Baronet

Knight

untitled landed gentry

tenant farmers

laborers

The titles duke, earl, viscount, and baron were for people called peers, who were qualified to be members of the House of Lords. The baronets and knights were not so qualified, but were considered to be members of the nobility, as were, with time, the landed gentry. Since anyone who was neither a member of the royalty nor a peer was a commoner, the lesser nobility were also commoners.

I should point out that the middle class is not part of the scheme. People who owned businesses were technically of the same rank as tenant farmers, but some of them had the wealth of high nobility.

Also, a person could have more than one title. So it was possible for a king also to be a vassal of another king because of a lesser title for land in a different country. The kings of England were vassals of the kings of France for centuries, because the kings of England were also dukes of Normandy and Aquitaine. The current Queen of England continues to bear the title of Duke of Normandy, though the territory of the Duchy of Normandy as been reduced to the Channel Islands.

In England, as in most other countries, all of these titles had female equivalents, and women could hold title in their own rights. Most of these are pretty obvious, but a couple were not. The title of countess was the female equivalent of an earl. The female equivalent of knight was usually dame, as opposed to the title for a woman who was the wife of a knight, whose title was lady. The exception to this was for the Order of the Garter, which used lady instead of dame.

For more information, please use the link below.