The Holy Coat of Trier (or Treves), Germany, a plain brown piece of cloth without visible seams, is a relic housed in the Roman Catholic cathedral at Trier. It has traditionally been identified as the coat Christ wore the last days of his life when he was arrested, beaten, and crucified. The earliest account of the coat dates from the twelfth century. The Gesta Trevirorum notes that the coat was presented to Bishop Agritius (314-334) by the empress Helena (c. 248 – c. 329). Helena was the mother of the Roman emperor Constantine, and she used her position to promote Christianity after her son legalized it in 312. She traveled to the Holy Land and reputedly recovered several relics associated with Christ, most notably the cross upon which he was executed. While more famous for her promotion of the True Cross, she also recovered the seamless coat for which the Roman soldiers gambled as Jesus suffered on the cross.
the relic stayed in Trier through the next centuries and was placed on display on several occasions during the sixteenth century, when its religious future was called into question upon the rise of Protestantism. (Several prominent Protestant leaders denounced the coat, noting that several rivals for the Trier relic were on exhibition at other European churches, most notably at Argenteuil, France.) During the continued unrest and wars of the seventeenth and eighteenth century, the coat was hidden away. Following Napoleon’s conquest of the region, in 1810 the local bishop felt confident enough to bring the relic from its then hiding place in Augsburg. It has since remained in Trier.
In the modern world, the Holy Coat has been the subject of a variety of critiques, many due to the audacious claim made about its origin. For many centuries, the case for authenticity was based on a document that lay in the archives of Trier, called the "Sylvester Diploma." However, this document, once believed to have been sent by Pope Sylvester I (r. 314-335), has not survived critical scrutiny and is no longer considered genuine. the fact of the coat’s being tied to Helena also ties it to other equally questionable Christian relics, not to mention the absence of contemporary fourth-century records concerning Helena and the Holy Land.
In the mid-1840s a piece of ivory, depicting the empress seated before the church and procession bringing a chest into the church, became the focus of a reexamination of the legendary depositing of the coat at Trier. The ivory, lost for many years, was found in 1844. In 1846 it was made available to the Archeological Society of Frankfort, which issued a statement fixing the ivory as originating in the fourth or fifth century. Noted Catholic historian Guido Gorres defended the relic in his pamphlet "The Pilgrimage of Treves," published in 1845.
To date, the coat has not been subject to the kinds of tests that other relics, such as the Shroud of Turin, have undergone. To complicate matters, in the nineteenth century, to better preserve the coat, it was immersed in a rubber solution. It is doubtful that such tests as carbon-dating, which might have helped date the item, could now yield satisfying results.
Since 1810 the coat has been placed on display at various times, and on each occasion hundreds of thousands of pilgrims have made the trek to Trier. The most recent showing was in 1996.