The Kalevala Day (Finnish: Kalevalan päivä), known as the Finnish Culture Day by its other official name, is celebrated each February 28 in honor of the Finnish national epic The Kalevala (Finnish: Kalevala). The day is one of the official Flag days in Finland. 
The Kalevala – the Finnish national epic
The Kalevala is a 19th-century work of epic poetry compiled by Elias Lönnrot from Finnish and Karelian oral folklore and mythology. It is regarded as the national epic of Finland and Karelia and is one of the most significant works of Finnic literature. The Kalevala has inspired artworks of many famous artists, including – for instance – music of the Finnish classical composer Jean Sibelius and the illustrations of the Finnish painter Akseli Gallen-Kallela.
The title The Kalevala can be interpreted as The Land of Kaleva or Kalevia. The first version of The Kalevala, called The Old Kalevala, was published in 1835. The later second version is the most commonly known version today. It was first published in 1849. It consists of 22,795 verses, divided into fifty poems/songs (Finnish: Runot).
The author of The Kalevala, Elias Lönnrot (April 9, 1802 – March 19, 1884), was a Finnish physician, philologist and collector of traditional Finnic oral folklore. The material for the compiling of The Kalevala was gathered by him from Finnic oral tradition carried from the distant past, including short ballads, lyric poems and mythology, during his several expeditions in Finland, Russian Karelia, the Kola Peninsula and the Baltic countries.
The earliest remaining written reference to Kaleva (a.k.a. Kalev, Kalevi, etc. in Estonia) is by many experts considered to be one found in Widsith, also known as The Traveller's Song, which also provides the earliest known written usage of the name Viking, with the spelling wicing. Widsith is a 6th or 7th century Anglo-Saxon poem – or song – of 143 lines, which became copied into the Exeter Book, a manuscript of Old English poetry compiled in the late 10th century. Widsith is for the most part a survey of the people, kings and heroes of Europe in the Germanic Heroic Age.
The Germanic Heroic Age corresponds to the Germanic Wars in terms of historiography, and to the Germanic Iron Age in terms of archaeology, spanning over the early centuries of the 1st millennium, in particular the 4th and 5th centuries, the period of the final collapse of the Western Roman Empire and the establishment of stable "barbarian kingdoms" larger than at the tribal level (the kingdoms of the Visigoths, the Franks and the Burgundians, and the Anglo-Saxon invasion of Britain). The Germanic peoples at the time lived mostly in tribal societies.
The following is stated in Widsith:
"Caesar ruled the Greeks, Caelic the Finns ... I was with the Greeks and Finns and also with Caesar ...".
Many historians and folklorists believe Widsith's "Caelic" to be a reference to the ancient Finnic ruler Kaleva/Kalevi, discussed in both the Finnish epic Kalevala and the Estonian epic Kalevipoeg. 
Kalevipoeg – the Estonian national epic
Following the publishing of The Kalevala, a similar Estonian national epic Kalevipoeg was completed in 1853. Due to censorship, it could not be published that year, but it became published in parts as a new and extended version during the years 1857–1861, and as a book in 1862. Kalevipoeg is based on ancient oral tradition within Ancient Estonia of legends explaining the origin of the world.
Within old Estonian folklore, a malevolent giant by the name of Kalevi – a.k.a. Kalev, Kalevine, Kalevipoiss, Kalevine posikine, Kalevin Poika – appears, battling with other giants or enemies of the nation. In addition to Widsith's Caelic, early written references to Kalevi are found in a list of deities published by the Finnish author Mikael Agricola in 1551 with the spelling Calenanpoiat and in Leyen Spiegel published by Heinrich Stahl in 1641 with the spelling Kalliweh.  Kalevi – in slightly varying spellings – in the Estonian epic Kalevipoeg is widely viewed to be the same hero as Kaleva in the Finnish and Karelian epic The Kalevala.
- "News, 3/3/2014" – "Kalevala Day - Finnish Culture Day 28 February", posted by the EMBASSY OF FINLAND, Bucharest, a part of the Ministry for Foreign Affairs of Finland: http://www.finland.ro/public/default.aspx?contentid=299691&contentlan=2&culture=en-US
- "News, 2/26/2018" – "Kalevala Day - Finnish Culture Day 28 February", posted by the EMBASSY OF FINLAND, Warsaw, a part of the Ministry for Foreign Affairs of Finland: http://www.finland.pl/public/default.aspx?contentid=372389&contentlan=2&culture=en-US
- "Widsith: Anglosaksinen muinaisruno". Authors: Osmo Pekonen and Clive Tolley. Published in Jyväskylä, Finland, by Minerva in 2004, ISBN 952-5478-66-1
- Lauri Honko, Religion, Myth, and Folklore in the World's Epics: The Kalevala and Its Predecessors, published by Walter de Gruyter, 1990, ISBN 3-11-012253-7