ENThe burial site of Saint Casimir (1458-1484) in the Cathedral of Vilnius became a place where an immense number of miracles were worked soon after the saint's death. Early sixteenth-century historical records mention votive offerings of wax and silver dedicated to the saint. The sources also emphasize miraculous divine powers of the holy relics. The coffin of St Casimir was first opened in 1604, but the body of the saint was first divided into portions after 1636 when the relics were translated to a chapel in the cathedral dedicated to the saint. In mid-seventeenth century members of the Youth Sodality of Naples as well as Jan Sobieski, King of Poland, and Cosimo III de’Medici, Grand Duke of Tuscany, obtained the relics of St Casimir. August III, King of Poland and Grand Duke of Lithuania requested a portion of the relics and received them in 1736. Despite these requests, it may be concluded that during the Baroque period, the relics of the saint were not widely venerated and divided up only occasionally. Those who wanted to posess themselves of portions of the body of St Casimir, even people of some mark, had to overcome serious obstacles. Both King Jan Sobieski and Duke of Tuscany, Cosimo III de’Medici had waited a year and a half before their request was granted. In return for the donation of St Casimirs relics to the city of Florence, Cosimo III sent to Vilnius a magnificent reliquary containing the relics of St Mary Magdalen de’ Pazzi. Historical sources suggest that in the nineteenth century the relics of the body of St Casimir were divided into portions more frequently. In 1838 a few portions of the saint's body, namely two teeth and ten bones, were extracted from the coffin. In 1878 one of the saint's vertebrae was extracted in order to be placed “in churches and altars.”.During the anniversary of St Casimir in 1922, the coffin containing his relics was presented in the main altar of Vilnius Cathedral for the adoration of the faithful. Prior to that it had been carried in a procession and opened. The relics had been shrouded “in new silk cloth”, deposited in a new “expensive wooden” coffin and sealed. At the same time the old cloth that had shrouded the relics was most probably divided up as a hallowed relic. In 1953, when the relics of St Casimir were translated to St Peter and Paul’s Church in Vilnius, bishop Kazimieras Paltarokas did not open the inner receptacle with the relics. In 1982 the pastor of St Peter and Paul’s, rev. Pranas Vaičekonis opened the coffin for renovation, but he did not break the seals of the “urn-like” container with the holy relics. Similarly, on 3 March, 1989, on the occasion of the relics’translation to the cathedral, the inner coffin remained untouched, only the seals were checked and a formal inspection statement was drawn up. During the anniversary of St Casimir in 2004 the saint’s sarcophagus was once again renovated and presented for public veneration. However, it was not opened during the renovation or later. Historical records note the following years when the inner coffin with the relics was opened: 1604, 1664, 1677, 1736, 1838, 1878 and 1922. This article enumerates historical donations of St Casimir’s relics as well as occasions on which they were presumably given away. The article also focuses on the items in the Cathedral Treasury that are related to the cult of St Casimir who was venerated for his curative and intercessory powers.