The Annual Customs of Dahomey (xwetanu or huetanu in Fon) were the main yearly celebration in the Kingdom of Dahomey, held at the capital, Abomey. These ceremonies were largely started under King Agaja around 1730 and involved significant collection and distribution of gifts and tribute, human sacrifice, military parades, and discussions by dignitaries about the future for the kingdom.
Tradition amongst the Fon in Western Africa, and among other ethnic groups, often had ceremonies in family lineages where all members of the family would gather for a feast, provide gifts to the eldest member of the family, and discuss issues pertaining to the family. As part of the religious Vodun practiced in the area, gifts and sacrifices to the spirits and ancestors would also be given. King Houegbadja (c. 1645-1685) changed this widespread practice during his reign by making it so that sacrifices or gifts to spirits would have to be done by the king.
King Agaja (1718-1740) further centralized the ceremonies under the king and the royal dynasty. Under Agaja, the Annual customs became the central religious ceremony in the kingdom, wide participation by most of the population was required, all family lineages were expected to provide gifts and tribute (sometimes considered taxes) to the ruler, and aspects of animal and human sacrifice were added to the practice. The traditional family lineage ceremonies were not allowed in the kingdom until after the royal ceremony was completed. After Agaja the ceremony grew larger, longer and more lavish by future kings.
The Annual Customs involved multiple elaborate components and some aspects may have been added in the 19th century. In general, the celebration involved distribution of gifts, human sacrifice, military parades, and political councils. Its main religious aspect was to offer thanks and gain the approval for ancestors of the royal lineage.
Another function of the Annual Customs was to raise money for the royal family and the kingdom as a whole. Based on the traditional customs of gift-giving to eldest members of lineage lines, the population of the kingdom provided gifts or paid tribute to the king. The king would then display the riches as a sign of the accomplishments of his administration. The wealth was provided and displayed not simply to enrich the kingdom but also to gain the approval of the ancestors. After the display, significant amounts of the gifts were redistributed to the population.