Saint Thomas Christian crosses are ancient crosses which belonged to the ancient community of Saint Thomas Christians of Indian sub continent who trace their origins to the evangelistic activity of Saint Thomas in the 1st century thus making it one of the oldest Christian communities of the world. Saint Thomas Christian crosses are broadly classified as Mar Thoma Sliba (Saint Thomas Cross),Persian Cross, and Nasrani Sthambam.
Mar Thoma Sliba are found at Kadamattom, Muttuchira, Kothanalloor, Kottayam and Alangad in the South Indian state of Kerala. Outside Kerala, they are found in Goa and Tamil Nadu in India, Anuradhapura in Sri Lanka and Taxila in Pakistan. Flowery Persian Crosses found at Kottakkavu, Pallipuram and Niranam. The large open air rock crosses known as Nasrani Sthambams are found at the frontage of many Saint Thomas Christian churches in Kerala. It is recorded that before the arrival of Portuguese explorers there were more than 150 Syrian churches in Kerala.
Mar Thoma Sliba is a Syriac term which means Saint Thomas Cross. Antonio Gouvea in the sixteenth century work, "Jornada" states that the old churches of Saint Thomas Christians were full of crosses of the type discovered from S. Thome (Mylapore). He also states that veneration of the cross is an old custom in Malabar. "Jornada" is the oldest known written document which calls the cross as St. Thomas Cross. The original word used is " Cruz de Sam Thome " meaning Cross of St. Thomas. Interestingly, Gouvea writes about the veneration of the Cross at Cranganore mentioning it as "Cross of Christians"