Scholars believe that Muziris, an ancient harbour located on the mouth of Periyar, coincides with modern-day Kodungallur.
Central Kerala and western Tamil Nadu in early historic south India was ruled by the Chera line of rulers.
                
The harbour was visited by navigators from all over the world, especially from the Mediterranean world.
The Roman Empire had a continuous trading connection with the West Coast of India.
Along with spices (pepper), commodities such as pearls, muslin, ivory, diamonds, silk and perfumes were acquired by the sailors from central Kerala.

A traditional belief among the ancient Christians in Kerala is that Apostle St. Thomas landed in or around Kodungallur in the middle of the 1st century CE and founded Seven Churches: Kodungallur, Niranam, Nilackal (Chayal), Kokkamangalam, Kottakkavu, Palayoor and  Aruvithura  – a "Royal Church".

Sometime between the 4th and 8th century, the Knanaya Community is believed to have arrived from the Middle East under the leadership of the Syrian merchant Thomas of Cana.
The community settled on the southern side of Cranganore and eventually established three churches in the names of St. Thomas, St. Kuriakose, and St. Mary.
The Knanaya left their settlement after its destruction during a battle between the Kingdom of Cochin and Zamorin of Calicut in the 16th century.

According to one tradition, a Cochin Jew colony in Malabar Coast, probably established before the 6th century BCE, attracted the Apostle to this region.
The native Muslim tradition holds that the Cheraman Mosque in Kodungallur, "built in 629 CE by Mālik bin Dīnār", is the oldest mosque in South Asia.
Scholars believe that Muziris, an ancient harbour located on the mouth of Periyar, coincides with modern-day Kodungallur. Central Kerala and western Tamil Nadu in early historic south India was ruled by the Chera line of rulers.                 
The harbour was visited by navigators from all over the world, especially from the Mediterranean world. The Roman Empire had a continuous trading connection with the West Coast of India. Along with spices (pepper), commodities such as pearls, muslin, ivory, diamonds, silk and perfumes were acquired by the sailors from central Kerala.
A traditional belief among the ancient Christians in Kerala is that Apostle St. Thomas landed in or around Kodungallur in the middle of the 1st century CE and founded Seven Churches: Kodungallur, Niranam, Nilackal (Chayal), Kokkamangalam, Kottakkavu, Palayoor and  Aruvithura  – a "Royal Church".
Sometime between the 4th and 8th century, the Knanaya Community is believed to have arrived from the Middle East under the leadership of the Syrian merchant Thomas of Cana. The community settled on the southern side of Cranganore and eventually established three churches in the names of St. Thomas, St. Kuriakose, and St. Mary. The Knanaya left their settlement after its destruction during a battle between the Kingdom of Cochin and Zamorin of Calicut in the 16th century.
According to one tradition, a Cochin Jew colony in Malabar Coast, probably established before the 6th century BCE, attracted the Apostle to this region. The native Muslim tradition holds that the Cheraman Mosque in Kodungallur, "built in 629 CE by Mālik bin Dīnār", is the oldest mosque in South Asia.
Kodungallur