The parish of St. Patrick came to life on July 21, 1974 when territory was taken from St. Thomas More and St. George to create a new spiritual home for some 450 families. Father Nicholas Martrain was named the founding pastor and a temporary home was found for the new congregation at the Episcopal High School chapel.
As the parish became organized, the parish council saw the need for an accurate census. They discovered that there were over 700 families within the boundaries of St. Patrick, not the 450 families given to the parish from St. George and St. Thomas More. With the census in hand, the Council made it their priority to assist Father Martrain in finding property for a permanent church, as well as planning how to fund the building of a church.
On December 18, 1977, the parish celebrated the Sunday liturgy in its borrowed quarters at Episcopal Chapel for the last time. The first Masses said in St. Patrick Church were on Christmas 1977. Bishop Joseph Sullivan dedicated the new church a few weeks later on January 8, 1978. The parishioners pitched in to do landscaping of the grounds. The crowning touch was the installation of the Pieta by Frank Hayden which was unveiled on Easter 1978.
Over the years, the parish continued to grow as new facilities were built and the population increased. A special tradition was started at St. Patrick when Bishop Stanley Ott surprised the parish by coming to celebrate Holy Thursday services just a few weeks after his installation as third Bishop of Baton Rouge on March 26, 1983. This visit became an annual tradition for the bishop.