The relics of one of Russia’s greatest heroes, Dmitry Donskoy, have been recovered at the Kremlin’s Archangel Cathedral, the Russian Orthodox Church announced on Tuesday.

Grand Prince Dmitry of Moscow has for centuries been revered for his victory over the Mongols at the Battle of Kulikovo on the Don River in the year 1380, which earned him the epithet Donskoy. While the victory did not end the Golden Horde’s domination over the Russian principalities, it is traditionally regarded as a turning point in Russian history that helped pave the way for eventual liberation.

Under Dmitry Donskoy, Moscow also strengthened its position as the leading power among the rival Russian principalities, laying the foundations for the emergence of a centralized Russian state. The Orthodox Church canonized the prince in 1988.

The Church said Donskoy’s remains were uncovered by chance during restoration work at the cathedral last month. The project was undertaken to address sinking floor slabs that threatened to damage the tombstones of several grand princes.

As workers dismantled the brick covers of the crypts beneath the floor, they uncovered three white-stone sarcophagi. One was found to have cracks requiring urgent repairs.

The discovery marked the first time Donskoy’s burial site had been opened. Until July, Kremlin museum specialists had been uncertain about the exact location of his remains after a 19th-century engineering report suggested that the tombs may have been mixed up.

With the blessing of Patriarch Kirill, archaeologists and anthropologists from the Russian Academy of Sciences examined the remains.

After the remains were authenticated, Kirill ordered that fragments of the relics be recovered and made available for veneration by worshippers.

During a special service on Tuesday, the patriarch highlighted Donskoy’s role in the emergence of a sovereign Russian state.

“Now we will offer a prayer to the holy and faithful prince, asking him to intercede for and protect our land, our Fatherland, and to beseech the Lord to safeguard the Russian land from every enemy and adversary,” the patriarch said.

Presidential aide and historian Vladimir Medinsky described the recovery of Donskoy’s relics as an event of profound spiritual significance for the entire nation, according to TASS.