Synod of Diamper

The Synod of Diamper, held at Udayamperoor (called Diamper in non-vernacular sources), was a diocesan synod or council that laid down rules and regulations for the ancient Saint Thomas Christians of the Malabar Coast (modern Kerala state), India, formally uniting them with the Roman Catholic Church. It was convened on 20 June 1599, under the leadership of Aleixo de Menezes, Archbishop of Goa. Archdeacon George of the Cross was forced to comply with the wishes of the Archbishop of Goa. This separated the Saint Thomas Christians from the Mesopotamian Church and subjected them directly to the Latin Archbishopric of Goa. The Archbishopric of Angamaly was downgraded to a bishopric under Goa in 1600 AD. Portuguese Padroado rule was thus imposed and the bishops for Saint Thomas Christians were appointed by Portuguese Padroado.

In 1597, Mar Abraham, the last Metropolitan Archbishop appointed by the Chaldean Patriarch, died. Archdeacon George of the Cross according to the custom and by virtue of appointment of Mar Abraham, took up the administration of the Archdiocese of Angamale. Menezes hastened to Nominate Fr. Francis Ros SJ as Administrator. In the end since the Archdeacon George ((കുരിശിങ്ങൽ ജോർജ്)) was well accepted by the people, Menezes had unwillingly reversed his decision and confirmed the Archdeacon as Administrator. Archdeacon called together an assembly of the Saint Thomas Christians at Angamali, in which a solemn oath was taken that they would act only according to the wishes of Archdeacon.

Menezes undertook a visit to all the Churches of Saint Thomas Christians in February 1599, which lasted for few months and slowly earned the good will of people. After having won over a considerable number of people and priests, Menezes threatened to depose Archdeacon, George (of the Cross) and appoint in his place Thomas Kurian, another nephew of former Archdeacon whose claims had been ignored in 1593. To prevent a division, Archdeacon, George (of the Cross) yielded to the demands of Menezes.

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