The celebration of the Greek Revolution of 1821 (), less commonly known as Independence Day, takes place in Greece, Cyprus, and Greek diaspora centres on 25 March every year, coinciding with the Feast of the Annunciation.

The day is a public holiday in Greece and Cyprus. Usually celebrations include parades and other celebratory events on the day or day before. The largest event is the military parade in Athens on 25 March, while on the previous day, celebrations take place throughout the schools of the country. In other municipalities parades of military divisions, students, clubs, etc. are held, as well as church services.

More broadly, the holiday acknowledges the successful Greek War of Independence (1821–1829) fought to liberate and decolonise Greece from four centuries of Ottoman occupation. After nine years of war, Greece was finally recognised as an independent state under the London Protocol of February 1830. Further negotiations in 1832 led to the London Conference of 1832 and the Treaty of Constantinople (1832); these defined the final borders of the new state and recognised the king.

The holiday was established in 1838 with a Royal Decree by King Otto's government.

When expressing celebration of the day, it is common to say "Long live Greece!" ()

History 25 March, the feast day of the Annunciation, had been chosen as the day of the start of the Greek Revolution against the Ottoman Empire, by the leader of the Filiki Eteria Alexander YpsilantisΣπηλιάδη Νικολάου, Απομνημονεύματα, εκδοθέντα υπό Χ.Ν.Φιλαδελφέως, Αθήνα 1851, τομ. Α', σελ. 31.: "... ο Κολοκοτρώνης και οι περί αυτόν, οι οποίοι δεν ήλθον εις την Πελοπόννησον ειμή δια να κινήσωσι την επανάστασιν την 25 μαρτίου, ως ημέραν προσδιωρισμένην να λάβωσι τα όπλα απανταχού οι Έλληνες, .Θεόδωρου Κολοκοτρώνη, Απομνημονεύματα (Διήγησις συμβάντων της Ελληνικής φυλής 1770–1836), έκδοση "Εστίας", 1901, τόμ. Α', σελ. 47, 48:Φωτάκος, Απομνημονεύματα, έκδοση 1858, σελ. 13: "Εις αυτούς εφανέρωσε (ο Αρχιμανδρίτης Γρηγόριος Φλέσας) τον ερχομόν του, τον τίτλον του ως απεσταλμένου παρά της Γενικής αρχής κτλ και ότι η 25 Μαρτίου είναι η πρώτη ημέρα της επαναστάσεως." "as evangelising the political liberation of the hellenic nation".Σπ. Τρικούπη, Ιστορία Ελληνικής Επαναστάσεως, έκδοση 1860, τομ. Α' σελ. 23. This date was considered a reference point since the early days of the Revolution, and even as the starting day of a new calendar, even in areas which had revolted earlier.Ιωάννης Φιλήμων, Δοκίμιον ιστορικόν περί της ελληνικής Επαναστάσεως, Αθήνα 1860, τομ. 3, σελ. 410.: Ημερομηνία σε έγγραφο της Κοινότητας Ήλιδος (Πελοποννήσου): "1821 Μαΐου 25, Κούκουρα της Γαστούνης, Έτος πρώτον από της 25 Μαρτίου". Since 1823 at the latest it was considered in the Peloponnese as the starting day of the revolution.Αρχεία Ελληνικής Παλιγγενεσίας, τ. 12, σελ. 157, 158.: "Το Επαρχικόν Κριτήριον Τριπολιτζάς. Ο Ν.Α. εις τους 1820, προ της επαναστάσεως, ... έφθασε εδώ εις Μορέα τον Σεπτέμβριον, η αποστασία ακολούθησε εις τας 25 Μαρτίου. Ακολούθου 1822 ο Μπηλελόπουλος, στοχαζόμενος την ευκαιρίαν της αποστασίας, απεφάσισε να καταφάγη όλην σχεδόν την ποσότητα των γροσίων ... με την πρόφασιν ότι την άρπαξαν οι Έλληνες εις τον καιρόν του ασάλτου. ... Τη 19 Αυγούστου 1823, Τριπολιτζά.

In 1822, the provisional government headed in Corinth decided to celebrate the anniversary of the Revolution the same day as Easter (2 April, Julian Calendar). The celebrations took place in Corinth with a military procession, festive church services and cannon fire, as described by the German volunteer Striebeck, who was present.C.T. Striebeck, Mittheilungen aus dem tagebuche des philhellenen, E.A. Telgener, 1834 (1η έκδοση 1828), σ. 187-189. Αναφέρεται στο Κ. Σιμόπουλος, “Πώς είδαν οι ξένοι την Ελλάδα του 21”, τ. 2, σ. 53. “Η κυβέρνηση αποφάσισε να συνδέσει την Ανάσταση με την επέτειο της εθνικής ανεξαρτησίας. Με το πρώτο χτύπημα της καμπάνας, που μόλις είχαν κρεμάσει στο μικρό καμπαναριό αντικαθιστώντας το ξύλινο σήμαντρο, συγκεντρώθηκαν χίλιοι περίπου άντρες μπροστά στην κατοικία του Μαυροκορδάτου. ... Πλάι στο Μαυροκορδάτο, στην αίθουσα των συνεδριάσεων, βρισκόταν κιόλας ο Υψηλάντης ... και όλοι οι υπουργοί και γερουσιαστές. Αμέσως μετά σχηματίστηκε η πομπή. Πεντακόσιοι άνδρες του ελληνικού πεζικού μπροστά – μαζί τους και οι ένοπλοι εθελοντές του εξωτερικού – ύστερα ο πρίγκιπας Μαυροκορδάτος ανάμεσα στο ιερατείο, οι γερουσιαστές και οι υπουργοί. Την πομπή έκλειναν άλλοι 500 στρατιώτες.

According to the writer D. Photiadis and others, before 1838, 1 January was considered the national holiday,Δημήτριος Φωτιάδης, Όθωνας - Μοναρχία, Ζαχαρόπουλος Σ.Ι, Αθήνα 1988, σελ. 367 a date which was voted on by the First National Assembly at Epidaurus the first Greek "Constitution", or the "Provisional Regime". It is therefore believed that by changing the date "the national holiday was losing its political and revolutionary character and taking on a religious nature" with whatever that entailed concerning the assertions of democracy and a constitution. The historian Chr. Koulouri, who researched national holiday-type celebrations from 1834 and after, does not include in them 1 January, but instead six dates related to the royal family. The main celebration before the establishment of 25 March was 25 January, the anniversary of King Otto's landing in Nafplio (1833).

The leader of the Filiki Eteria who organised the revolution, Alexander Ypsilantis, kickstarted the operations in Iasi on 24 February 1821. However, the events there were characterised in the collective conscious and history as something isolated, something like a prologue to the Revolution. The complete failure of the movement in a non-Greek area, maybe also the disappointment of the Greeks about the delusion of Russian support propagated by the Filiki Eteria, were the main contributors to the distinction between the events in the Danubian Principalities and those in Greece. The State validated the prevailing attitude and chose 25 March as the national holiday.Δασκαλάκης Β. Απόστολος, Η έναρξις του Αγώνος της ελευθερίας. Θρύλος και πραγματικότης. Επιστημονική Επετηρίς της Φιλοσοφικής Σχολής του Πανεπιστημίου Αθηνών, τόμ. 12 (1961–1962), σ. 9.

According to certain views, the starting date of the Revolution is indeed 24 February, when the Greek revolution in Wallachia started with Alexander Ypsilantis' proclamation Fight for Faith and Fatherland. Since then and with other revolts which took place well before 25 March the Greek Revolution was spread throughout Ottoman Greece, until it reached the Peloponnese.

In Greece skirmishes had started before 25 March, as is recorded in the news which have been preserved in the "Correspondence of the Dutch Embassy in Patras: 1821", the Dutch government having been informed through its ambassador in Patras on 23 March that "since this year a latent dangerous situation has broken out" and that "the Greeks took up arms against the dynast".

The official declaration of the revolutionaries to foreign governments happened with the proclamation of the "Messenian Senate" on 25 March 1821.Φιλήμων Ιωάννης, Δοκίμιον ιστορικόν περί της ελληνικής Επαναστάσεως, Αθήνα 1860, σ. 29.Σπυρίδων Τρικούπης, Ιστορία της ελληνικής επαναστάσεως, έκδοση 1888, τομ. Α', σελ. 253. The 25th/3rd is considered the start of the Revolution in an 1823 judicial document of the Provisional Government of Greece, where the "Provincial Criterion of Tripoli" (a judicial body) mentions that "the rebellion followed on 25 March".Αρχεία Εθνικής Παλιγγενεσίας, επανέκδοση 1971, τομ. 12, σ. 157.

Institutionalisation Panagiotis Soutsos was the first to suggest in 1834 the establishment of the celebration of the Greek Revolution on 25 March, mentioning that it was the day of the spread of the revolution throughout the Peloponnese and the rebirth of Greece, in a petition which Ioannis Kolettis submitted to Otto as a proposition of a law draft. Kolettis', the Foreign Minister, document, is dated 22 Jan./2 Febr. 1835 and suggests to the King to establish celebrations with panhellenic games similar to those of ancient Greece. His proposal is written in French with a German abstract. It mentions that "renowned Germanos" (celebre Germanos) proclaimed the Revolution on 17 March 1821 in Agia Lavra, and that the revolution spread throughout the Peloponnese on 25 March, which he considers the day of the start of a new era for Greece. He even says that there was a prophecy of the monks of Mega Spilaio that on this date the rebirth of Greece would take place, and that the Ottomans of the Peloponnese knew about it and every year on this date they took emergency security measures (Diamantis, p. 314). The celebrations proposed by Kolettis included competitions in the arts and sciences and in various sports. They would take place in Tripoli, Athens, Hydra and Mesologgi, alternating between the four each year, for a full cycle of four years, similarly to the ancient Olympic, Pythian, Isthmian and Nemean games.Διαμαντής Αθ. Κωνσταντίνος, Πρότασις καθιερώσεως εθνικών επετείων και δημοσίων αγώνων κατά το πρότυπον των εορτών της αρχαιότητος κατά το έτος 1835, "Αθηνά", Σύγγραμμα περιοδικόν της εν Αθήναις Επιστημονικής Εταιρείας, τομ. 73, 74 (1972, 1973), σελ. 307-325. In 1836, 25 March was honoured together with Kalavryta and Germanos with a bronze medal which was minted for the occasion of King Otto's marriage to Amalia of Oldenburg. On it is the legendary scene of Germanos raising the flag and the cross and two armed fighters in an oath or saluting stance. It bears the inscription: "MY FATHER'S GOD AND I WILL EXALT HIM – KALAVRYTA 25 MAR. 1821" (το απόφθεγμα είναι από την Έξοδο, ιε', 3). The other side of the medal depicts Germanos.Meletopoulos J., Twelve Greek medals, Αθήνα, 1971.

The celebration "from then on forever" of the Revolution on 15 March was established in 1838 with Royal Decree 980 / 15(27)-3-1838Πέμπτη, 24 Μαρτίου 2011, Ο πρώτος πανηγυρισμός της Εθνικής Εορτής στις 25 Μαρτίου 1838 στην Αθήνα, Μιχ. of the Otto government and specifically that of Georgios Glarakis, Secretary of State for Ecclesiastical, Public Education and Internal Matters. Glarakis was one of the main representatives of the Russian Party, the "Napists", which during this period was favoured by Otto. Otto was trying to boost his popularity by associating himself with the popular expressors of Orthodoxy, and this may be the reason for the religious nature of the decree and the establishment of the holiday. However, on the first celebration of the anniversary, in 1838, the only foreign ambassadors missing were those of Russia and Austria.Μαρκεζίνης Β. Σπ., Πολιτική Ιστορία της Νεωτέρας Ελλάδος, τομ. Α', σ. 161.

The first celebration took place in Athens which was attended by King Otto and Queen Amalia, political and military authorities and a mass of people. The Metropolitan Church of Athens was built on 15 December 1842 and was dedicated to the Annunciation in order to honour 25 March 1821.Εφημερίδα "Αιών", 1 Ιαν. 1843, σ. 2, στήλη αριστερά.Μαρκάτου Φ. Θεοδώρα, Οι προτάσεις για πανελλήνιο ηρώο του Εικοσιένα (1830–1930), "Μνήμων", τ. 17 (1995), σ. 46.

In 1839, Amvrosios Frantzis mentions that 25 March was a day "clear and embedded in the heart of Peloponnesians as the starting day of the Greek revolution".

Later After the official establishment of the holiday, and especially in 1841, there was an attempt by the anti-Otto opposition to expropriate the anniversary, with private celebrations where Korais' figure was especially celebrated. The holiday continued to be a matter of political and localist conflict; Prime Minister Kolettis' decision in 1846 and 1847 to hold an official ceremony on the grave of the Rumelian chieftain Georgios Karaiskakis in Phaleron caused major reactions, as it was considered as leading to identification of the Revolution with one individual.

Celebrations in Greece and Cyprus