The Trikkakara temple dedicated to Vamana, the fifth incarnation of Vishnu, was founded and renovated in 604 A.D. The Edapalli (a small kingdom in the vicinity of Cochin) chiefs were its priests. On account of their sambandham or marriage alliance with the princesses of Perumpadappu Swarupam or Cochin Royal House
annual Onam festival in the month of Chingom (August- September) became important for
these royal But in the 15th century the relations between families were strained as a
result of which the Perumpadappu chiefs allied them - selves with the Zamorin.
Thereafter the festival became important for the Zamorin's
family. In course of time the temple got endowments from every part of Kerala. In ancient
Kerala it was the duty of the temple tenants, to whatsoever religion or caste they might
belong, to attend its annual festival. Those living far away celebrated the festival in
their own homes if they could not be present at Trikkakara. Thus the Trikkakara festival
became the national Onam festival. Onam is still celebrated as the national festival of
Kerala but not in the manner described above.