Arnas, also known as Arnes, Urdnus, or by its Turkish name Bağlarbaşı, is situated 9 kilometers northeast of Midyat in the Tur Abdin region. The village is home to the church of Mor Quryaqos, which dates back to 761.
70 Syriac-Aramean families resided here alongside a Kurdish majority that included Osman Tammero, the leader of the Dakshuri confederation. While most of these families belonged to the Syriac Orthodox Church, 10 were recorded as Protestant.
Upon learning of the destruction of nearby Saleh and hearing gunfire from the direction of Midyat, the Syriac-Aramean inhabitants gathered what they could carry and fled. Local Kurdish forces attempted to intercept them, but the large group successfully forced their way through and escaped to Iwardo. However, 23 Syriac-Aramean men who remained in Arnas were murdered the following day.
