The origin of Thalasserry province is closely connected with the history of Kerala. During the years that followed the World War II, groups of Catholic families from Kottayam and Alappuzha Dts. migrated to Malabar, seeking virgin land for cultivation. As most of the families belonged to the Syro-Malabar Church, the authorities decided to have a Syro-Malabar Diocese for the Malabar region in 1953. Vatican appointed Bishop Sebastian Vallopilly from Palai as the first Bishop of the new diocese.
The new Bishop realized that for the all around development of the area and families the service of the Sisters would be needed. Hence he approached various congregations in Palai to send sisters to serve in Malabar. Malabar filled with hills and forests that inhabited wild animals was feared by all. First the major superiors refused to send sisters, fearing for their safety. However, then Mother General, Mother Celestina agreed to send four sisters to serve in Malabar. The Bishop sent them to Kaniyaram in Waynad. Rev. Fr. George Kazhikachalil did all he could to accommodate them.
The extreme cold climate with very little facilities for stay made the life of the first missionaries very hard. But, they were fired with mission spirit and encouraged the superiors to send more sisters. The next year more sisters came and more convents were started. The Fathers and Sisters worked together for the total development of the area, conducting schools and making roads. More parishes requested the service of the sisters and young sisters came with great zeal and enthusiasm. Some of them returned to the Mother provinces and majority of the sisters from Palai stayed, accepting the challenges of working with limited facilities and extreme poverty. Over the next few years, the number of sisters and convents increased in the Malabar area. Local vocation was encouraged and they went to Palai for formation and returned with renewed spirit. In 1964, combining all the convents in Malabar, a Region was formed and Sr. John Viany from Palai was appointed as Regional Superior. In 1965 it became a commissariat, making Kilianthara convent the head quartes. Mother Flavia from Changanacherry was appointed as the Commissary. The Malabar region was developing fast and the Church, priests and sisters, played a major role in its development.