The cathedral church, named in honour of St. Hyacinth of Poland, was built in 1880 in the Romanesque Revival style.

Realizing that the debts of his cathedral called for unusual measures, he closed the episcopal palace and retired with his staff to Saint-Mathieu-de-Beloeil, where he combined the duties of bishop and pastor.

[3] The construction of the current building was undertaken by Bishop Louis-Zéphirin Moreau, with the money saved by the economy of his predecessor.

After the Second Vatican Council various elements of the choir were rearranged; Czechoslovakian glass chandeliers were hung, replacing neon light fixtures.

In 1853 by Mgr Ignace Bourget, bishop of Montreal, presented Saint-Hyacinthe with a harmonium that was used until the installation of the Casavant organ, opus 8, in 1885.