Primogeniture is a historical term that refers to the rights and responsibilities of the first-born child among siblings in a family. When used in the legal sense, the term is used to discuss the right of the eldest son in the family to inherit his parents’ estate upon their death. The initial purpose of determining primogeniture was to keep an estate from being divided among siblings. When this was done, a parcel of land would continue to get smaller and smaller, which reduced the value of the overall property. To explore this concept, consider the following primogeniture definition.

Definition of Primogeniture


  1. The state of being the firstborn child in the family.
  2. The system of inheritance or succession of the firstborn child, especially the eldest son.


1585-1595       Medieval Latin prīmōgenitūra (“a first birth”)

Primogeniture Law

Primogeniture law historically determined that the first-born son among all of a couple’s children would inherit his parents’ entire estate upon their deaths. The purpose of this was so that the parcel of land would not end up being so subdivided that the value of each individual parcel would plummet.

The term “primogeniture” was implied to refer to male children. If there were no male heirs, then primogeniture law determined that the property would be divided up among the daughters in equal shares. Primogeniture law actually hails from feudal England, and does not exist in the United States.

Primogeniture and Ultimogeniture

While primogeniture refers to the eldest son inheriting his parents’ estate, ultimogeniture refers to the exact opposite: the youngest son inheriting the estate. It is very rare, but primogeniture can also refer to the eldest daughter taking over full responsibility for the property. Both practices are commonly used by those who work in agriculture. This is particularly true for those living in areas where the population is steadily increasing, but they are running out of land for people to live on.

In these cases, the main concern is also that the land would be split up into such tiny parcels that they would be too small to support farming efforts. In certain cases, the designation of a sole heir to a property has forced the remaining siblings to fend for themselves.

Primogeniture has also been relied upon in certain political situations. For instance, in Egypt, primogeniture sometimes led to a succession of power and a political office, rather than to the inheritance of a physical possession like land.

Since ancient times, primogeniture has typically been chosen over ultimogeniture as a way to maintain respect for the elder in the family. However, ultimogeniture may be deferred to if the youngest son has lived in his father’s house the longest. Similarly, he may be the preferential candidate if he is the least established, meaning that he has not cemented a career for himself, or started a family.

Some courts of law saw the advantages in the youngest son statistically having more years of life remaining than his siblings. In the case of ultimogeniture taking precedence, the older brothers in the family may be compensated in other ways. Such compensation may take the form of privileges and advantages related to authority, tangible materials, or finances.

Primogeniture Example in Royal Succession

Throughout history, the determination of who would wield the crown in a hereditary monarchy most commonly followed the rule of primogeniture. This saw the monarch’s eldest son being groomed from birth to take the throne, even if he has older sisters. Such a child often received preferential treatment, but was saddled with additional responsibilities and educational requirements as well.

In a primogeniture system of royal succession, the right of succession belonged to the eldest son, and then to his eldest son, and so forth. This means that, should something happen to prevent the eldest son from taking the throne – such as his death – the right would fall to his own son, rather than to his younger brother.

For example:

King Edvard’s first two children were girls, followed by a son – Edvard II – then two more boys, Henry and Gerald. When the king dies from a heart attack, the kingdom’s primogeniture tradition sees the throne fall to Edvard II, as he is the eldest son.

Edvard marries and has three children of his own – all boys: Edvard III, William, and Benedict. One day Edvard II is killed in a hunting accident and, although his children are still young, the throne goes to his 10-year-old son, Edvard III, rather than to his brother, Henry. In such examples of primogeniture, it was common for the king’s brother or other relative to manage the nation until the young king-in-waiting reaches the age of majority.

Related Legal Terms and Issues

  • Estate – An extensive area of land, usually with a large house, belonging to a family; all of the money, property, and possessions belonging to a single person.
  • Inheritance – Something passed down to a person from his or her parents.
  • Monarchy  – A form of government in which a specific group or family heads up the country.
  • Succession – The right or process by which a person succeeds – or rises to – the office, rank, or role of another.