In 1552 King Dharmapala received baptism and embraced Christianity together with 70,000 coastal community that included Christians from Palliyawatta.
During the time of Portuguese the Catholics here at Palliyawatta were belonging to Modera Parish. (Christian community at Modera)
The time from 1543 to 1658 the coastal areas in Sri Lanka were under the care of the Franciscan missionaries from Portugal.
In the year 1658, the Dutch captured the areas under Portuguese. As a result the church at Modera was destroyed but a good Christian community persevered.
In the first week of March 1698 the Lankan Apostle Joseph Vass arrived here. He offered mass under a big Tamarind (siyambala) tree, located near the Kelani River and the Hamilton Canal.
The Ivory statute of Our Lady of Mount Carmel donated by Joseph Vass is a living testimony of the faith of the people at Palliayawatta (Wellapalliya Parish).
In the time of Dutch persecution from the year 1698 to 1796 Fr. Joseph Vass together with the other missionaries belonging to the Oratorian Congregation worked secretly for the good of the people. At this time Palliyawatta was a part of Aluthkuru Korale. (The locality was called such)
In year 1796 the British seized the coastal areas from the Dutch.
In the year 1816, the Modera church was constructed and the missionary work was carried out with renewed zest and vigour.
In the year 1828 the Superior General of Oratorion Congregation, Fr. Francis Xaviour sent a detailed report to the Holy See about the churches and the chapels existing in Sri Lanka. In this report he also mentioned about Wellapalliya Parish.
In the year 1834 Sri Lanka was separated from the Arch Diocese of Kochin. So it was kept under the direct care of the Holy See.
In the year 1842, the Vicar for Sri Lanka his Lordship Gayathano Antonio sent a report to the Holy See and even in this report he mentioned about an existing small building (small church) dedicated to Our Lady of Mount Carmel at Palliyawatta.
In the year 1851 Wellapalliya was under Pamunugama Mission.
In the year 1853 the Oratorian Congregation in Goa completed their missionary work in Sri Lanka and the Benedictine order started their missionary work here in Sri Lanka.
On 17 March in the year 1863, His Lordship Giyachinto Welgera belonging to the Carmel order visited Wellapalliya church.
In the year 1866 Fr. Sylvester from Benedictine Congregation built the present day Wellapalliya church and initiated the church dedicated to St. Lazarus at Hekiththa.
In the year 1883 the Benedictine concluded their missionary work in Sri Lanka and the Oblates of Mary initiated the Arch Diocese of Sri Lanka.
In the year 1884, at the premises of the leprosy hospital, started building the church dedicated to St. Francis Xaviour.
In the year 1886 Palliyawatta was removed from Pamunugama and placed under Wattala Mission.
On 16 July in the year 1886 initiated the Association of Our Lady of Mount Carmel at Palliyawatta Church.
In the year 1904 the Association dedicated to Sacred Heart was established at Palliyawatta Church.
On 9 March in the year 1913 there was a miraculous thing as the Tamarind (Siyambala) tree was cutting under which Fr. Joseph Vass celebrated the Eucharist. With the collection received from the people who came to see the miracle the mission house was built on January 22 in the year 1914.
In the year 1914, the sisters of Our Lady arrived for the service at the leprosy hospital.
From 1914 to 1932, Wellapalliya and Nayakakanda were made semi Parishes.
In the year 1917, the Good Shepard Sisters established a convent at Palliyawatta. Earlier it was belonging to the Order of Francis Xaviour.
In the year 1918 Fr. C. Krocktain OMI initiated the Association of Holy Family.
In the year 1932 Wellapalliya was declared as a new parish and Fr. F. Bugaral was the first parish priest.
On 8 December in the year 1939 Children of Mary (Daru Samagama) of Our Lady was established.
On 5 April in the year 1945 when Fr. Nicholas Perera was the parish priest the historical cross was brought here.
Since 1948 Palliyawatta was placed under the Archdiocese of Colombo and Fr. Gerard Abesekara became the first Diocesan Parish Priest. He worked hard to get the Electricity to the Church and to the whole village.
On 15 March in the year 1964, the government suspended the service of the Sisters in the leprosy hospital.
In the year 1966 Fr. Solomon Perera, started building the present day church at Hekithta, the old church at Dickovita and both sides of the Wellapalliya church.
In the year 1967 Fr. Sixtus Kurukulasuriya established the first parish council here at Wellapalliya basing on the directives given by the Second Vatican Council.
On 15 August in the year 1987 The Salesians of Don Bosco started the mission here at Wellapalliya. Fr. Emmanuel Janze was the first parish priest.
This was the beginning of a new era and initiated the Jubilee celebration for the first time.
The parish was also blessed by its first priest in the person of Fr. Sarath Nimal Abesiriwardana.
On 18 and 19 July in the year 1992 celebrated the 150 year Jubilee and the church was renovated beautifully.
On 30 May in the year 1993 the church was blessed and the dedication of the Alter was done.
On 18 August in the year 1996 then the Archbishop of Vellur His Lordship Chinnappa Rayappu arrived at Palliyawatta and granted the Confirmation to 114 students.
In the year 2010 the Association of Our Lady of Mount Carmel commemorated the 125 years of its success.
In the year 2012 the Relic of Don Bosco arrived here at Palliyawatta.
On 09 June in the year 2013 the present day church at Dickowita was blessed.
On 21 April in the year 2014 the church dedicated to St. Joseph Vass was built.
On 16 July in the year 2017 in a grand scale celebrated the Jubilee of 175 years. The church was fully renovated for this event.