The word gala began as an Arabic robe of honour
Gala comes from khil'a, an Arabic word for a ceremonial robe, and only became a synonym for festival in the 18th century. The word festival itself was an adjective for two centuries before anyone used it as a noun. The events are far older than the vocabulary.
A festival is a community celebration built around some defining piece of its religion, customs or culture, whether a national holiday, a religious feast or a fair, which in South Asia is called a mela. Agriculture has been one of the biggest sources. Food matters so much that many festivals cluster around harvest, which is why autumn thanksgivings coincide with Halloween north of the equator and Easter south of it.
In English, festival arrived from Latin through Old French in the late 14th century, first describing things, so a festival dai was a religious holiday. The earliest recorded noun use dates from 1589, spelled Festifall. Feast is older, used as a noun from around 1200 and as a verb from about 1300. Most festivals still end in shared, specially cooked food, keeping the old link to feasting alive.
The Greeks and Romans leaned heavily on festivals for civic and administrative life, and the Roman Saturnalia probably fed into both Christmas and Carnival. Victories inspired them too: the Egyptian pharaoh Ramesses III founded one to celebrate defeating the Libyans. Some traditional festivals in Ghana predate European colonisation in the 15th century. They flourished after the Second World War, and two events founded in 1947, the Avignon Festival and the Edinburgh Festival Fringe, did much to set the modern pattern. Arts festivals grew more prominent around the turn of the 21st century.
People attend for escape, company and a sense of belonging, and cultural festivals let elders pass stories on to younger relatives. Before mass entertainment, they were a community's main amusement. Counting them is practically impossible, because the overwhelming majority are small, local and populist, and they refuse neat divisions into sacred or secular, rural or urban.
Source: Festival