J'ouvert (/dʒuːˈveɪ/ joo-VAY) (also Jour ouvert, Jouvay, or Jouvé) is a traditional Carnival celebration in many countries throughout the Caribbean. The parade is believed to have its foundation in Trinidad & Tobago, with roots steeped in French Afro-Creole traditions such as Canboulay. J'ouvert typically begins in the early morning, before dawn, and peaks by mid-morning. The celebration involves calypso or soca bands, DJs, and their followers dancing through the streets. In many countries, revelers cover their bodies in paint, mud, or pitch oil. Today J'ouvert is also a part of Carnival celebrations outside of the Caribbean, with the biggest celebrations happening in cities with large Caribbean ex-pat communities.

J'ouvert is a gallicization of jou ouvè (IPA [ʒu uvɛ]; jour ouvert in standard French), the French Creole term meaning "dawn" or "daybreak", as this is the time at which the celebration is typically held.

The origins of J'ouvert can be traced back to Trinidad. French traditions from the island's original Carnival, African and Afro-Trinidadian traditions from Canboulay, and various social and political influences maybe have all played a role in shaping J'ouvert.

J'ouvert's is rooted in the history of Carnival in Trinidad. The French brought Carnival to Trinidad in the 1780s, a time of slavery. Their pre-lenten Carnival included hunting parties, dinners, balls, and masquerading. Enslaved Africans, who were banned from participating in Carnival, are said to have staged their own mini-carnivals, but using their own rituals and folklore and imitating or mocking their masters' masquerade balls. These imitation carnivals and mocking of the ruling class likely gave rise to J'ouvert traditions, as parodying of the upper class is an important aspect of J'ouvert tradition. Alternatively, J'ouvert masquerading traditions may come from directly a French Carnival tradition that took the form of "after-dinner raids on private homes". Friendly raiders would disguise themselves in humorous costumes that were often topical, parodying political or social events, and would remain disguised until their identities were guessed correctly. Costumes with political and social commentary are still seen in J'ouvert today.

Before Emancipation, enslaved Africans in Trinidad had celebrated Canboulay, a night-time harvest festival characterized by drums, singing, calinda dancing, chanting, and stick-fighting. The term "Canboulay" comes from the French cannes broullee, meaning "burnt cane". It may refer to the putting out of cane fires, the pre-harvest cane burning for pest control, or the burning of cane as an act of sabotage during the time of slavery. Slavery was abolished in Trinidad and other British territories in 1833, with Emancipation taking effect 1 August 1834. After Emancipation, Canboulay developed into a festival for freed slaves and former indentured laborers to celebrate freedom. It was celebrated annually on Emancipation Day.

In 1881, the British colonial government on Trinidad attempted to ban Canboulay. This resulted in disturbances known as the Camboulay Riots, which took place in Port of Spain, San Fernando, and Princes Town. It is said that people smeared themselves with oil or paint to avoid being recognized, or may have been covered in black soot from burning cane. Today, covering bodies in oil, paint, or other substances is a distinctive tradition of J'ouvert. This tradition was likely carried forward in remembrance of the Canboulay Riots.

In 1884, the colonial government passed the Peace Preservation Act, which prohibited public carrying of torches, drumming, blowing horns, and stick-fighting (or the assembly of ten or more people with sticks). Many J'ouvert traditions may come from reactions to the prohibitions of the Peace Preservation Act. For instance, tamboo bamboo was introduced in the late 1880s as substitute for the drums and sticks. Tamboo bamboo bands developed and became the primary percussion instrument of Carnival. Additional instruments were developed to replace the banned drums, and percussion was achieve through use of metal and other items as well. The history of J'ouvert's improvised instruments is celebrated today with the use of whistles, cowbells, bottles, and home-made instruments.

The Peace Preservation Act also established the official start of Carnival as 6:00 A.M. This likely explains the early-morning start time of J'ouvert. Canboulay had traditionally been a nighttime celebration, but after the Peace Preservation Act effectively banned Canboulay, Afro-Trinidadians began celebrating a reinterpretation of Canboulay beginning at 6:00 A.M. on Carnival Monday. Some historians claim that revelers took advantage of the pre-dawn darkness and began festivities before 6:00 A.M.—and that this secret and rebellious celebration is the origin of J'ouvert. Today, J'ouvert in the Caribbean typically begins before dawn.