March 3, Bulgaria's national day, symbolises the restoration of the third Bulgarian kingdom after almost 500 years of Ottoman rule. The treaty of San Stefano, signed on March 3 1878, was the milestone of this process and the day remains one of the most celebrated in Bulgaria's history.  The San Stefano treaty ended the Russo-Turkish, which started in 1877.

Russian troops crossed the Danube River and invaded Bulgarian ethnic territory in the southern city of Svishtov.

In late July 1877, the Russian offensive was held up and the Turks launched an energetic counter-offensive.

At that critical moment, the assistance of the Bulgarian population was crucial. This was the moment that later gave grounds for Bulgarians to rightfully claim that their freedom was not a gift from the Russians.

The Bulgarians provided supplies to the Russian troops, helping them traverse the mountain regions, digging defences and collecting intelligence data. Armed units were sent to the enemy's rear. The Bulgarian volunteer unit, called "Opalchentsi", fought side by side with the Russian army against the Ottoman troops.

The battle for Shipka Pass in the Balkan Range was to crucially impact the course of military operations. It remains a battle revered by all Bulgarians.

In August, a battalion of Russian troops and Bulgarian volunteers miraculously managed to defend the pass from the powerful army of Suleiman Pasha, which was attacking from the south. Despite their numerical superiority, the Turks suffered a catastrophic defeat, while the defenders of Shipka worked miracles of bravery. At periods of complete despair and lack of ammunition, the defenders of the pass threw stones, tree trunks and the bodies of killed soldiers against the enemy.

A Russian detachment arrived just in time, providing crucial psychological support to the defenders. They counterattacked and sent the enemy running.

The Shipka battles became known to the world. Foreign reporters informed millions of readers about the course of the war. After Shipka, successful operations followed in Pleven, Sofia, Plovdiv and Shipka-Sheinovo and at the end, the Turkish command asked for peace.

On March 3 1878 in San Stefano, a village near Istanbul now called Yesilkoy, Turkey signed a preliminary peace treaty. Under this treaty the Bulgarian ethnic territories in Macedonia, Moesia and Thrace were liberated, and the Bulgarian state was restored after almost five centuries of Ottoman rule.

This treaty confirmed the creation of a Bulgarian principality. And while it was still under vassalage to the Ottoman Empire, it also had full internal independence, including all territories with a predominantly Bulgarian population. Its prince was to be elected by the Bulgarian people and endorsed by the Great Powers.

In this way, the San Stefano treaty resolved the ethnic and territorial problems in the Balkans, Konstantin Subchev, a historian, said in one of his essays on the subject.

Russia, however, was not in a capacity to uphold its positions.

Before the outbreak of the war, Russian diplomacy had already familiarised itself with the position of the other Great Powers, first and foremost Great Britain and Austria-Hungary, regarding the parameters of a future peace treaty. London and Vienna were insistent: they did not want the creation of a large Slavic state in the Balkans.

However, the brilliant Russian offensive in the winter of 1877-78 and the complete fiasco the Ottoman Empire faced inspired St. Petersburg with confidence, Subchev wrote. That is why the San Stefano treaty was called preliminary.

The real peace treaty, settling the borders in the Balkans with the involvement of all European Great Powers, was to be signed in Berlin on July 13 that same year.
The Treaty of Berlin was a complete disaster for Russian diplomacy and a bitter disappointment for all Bulgarians.

Under the Berlin treaty, only northern Bulgaria and the Sofia region were granted practical freedom and were included in the Principality of Bulgaria.

The remaining ethnic territories, which today represent parts of the Republic of Bulgaria, were incorporated later, following the long liberation and unification struggles.

Nevertheless, the disappointment from the treaties of Berlin and San Stefano and March 3 1878 will always be regarded as one of the secret moments of Bulgaria's history, as on that date and in that place Bulgaria was born again.