Tiraz is an embroidered textile worn at court, meant to signify honor and importance. For an introduction to tiraz, see this site.
This one is dated to 895, the same year that the ‘Abbasid caliph Mu’tadid married the daughter of the Tulunid emir. Khumarawayh’s daughter Qatr al-Nada (Dewdrop) went in great state to Baghdad and the wedding is famous in Islamic history for the vast amounts of money spent on her dowry and on entertainment by her father.
This one has the inscription in red silk, naming Abbasid caliph al-Mu’tadid bi’llah (ruled 892-901) and the Tulunid ruler of Egypt Harun ibn Khumarawayh (ruled 896-904). It was made in Tinnis in 900-1.