Archbishop Olçomendy came from the Basque Country in France, where he was born on 29 August 1901. He was ordained as an MEP Priest on 29 May 1926, after which he left France on 12 September the same year, heading to the Diocese of Malacca. During his one-year stay at the Church of St Anthony, Kuala Lumpur, he learned English and Tamil. This served him well when he was transfered to St Louis Church in Kota Taiping as he was able to minister to the Tamil-speaking Catholics around Taiping and surrounding rubber estates.
In 1937, he began his 10-year service in the Church of Our Lady of Lourdes in Singapore. Concurrently, he ministered to mainly Indian Catholics in the Seletar Air Base. He served as Vicar General of the Diocese of Malacca. Upon the passing of Bishop Adrien Devals during World War Two, it fell to Fr Olcomendy to shoulder the responsibility of administering the diocese. Two years later on 1 June 1947, he was consecrated as Bishop of Malacca, in the Cathedral of the Good Shepherd.
Following his appointment and consecration, Bishop Olçomendy had to deal with many complex administrative issues. One major challenge was the problems arising from the dual administration existing since 1887 by which the Catholics in the Church of St Joseph (Victoria Street) fell under the authority of the Bishop of Macau. Bishop Olçomendy pushed hard for a single administration. While this matter was resolved later under the term of his successor, Archbishop Gregory Yong, it was Olçomendy’s efforts which laid the groundwork for the eventual separation of St Joseph’s Church from the Macau diocese.
The Catholic population had also grown during Bishop Olçomendy’s term, making it challenging for one Bishop to oversee the entire diocese. This justified the division of the Diocese of Malacca. On 19 September 1955 the Diocese of Malacca was elevated to an Archdiocese, with Bishop Olçomendy serving as Archbishop. On 25 February 1955, the Archdiocese of Malacca became an ecclesiastical province which consisted of three regions namely: the Diocese of Penang, the Diocese of Kuala Lumpur and the Archdiocese of Malacca-Singapore. In 1972, due to political changes in Malaysia and Singapore and the large numbers of Catholics, the new Diocese of Malacca-Johor was established, detached from Singapore which became an Archdiocese.
Archbishop Olçomendy’s term also saw the opening of many churches in Singapore, namely the Church of St Bernadette in 1959, Church of St Ignatius in 1961, Blessed Sacrament Church in 1965, the Church of the Risen Christ in 1971. These new churches were needed to serve the spiritual needs of the growing Catholic population in the new housing estates which were emerging in various parts of Singapore In view of the new demographic landscape, the previous practice of assigning each parish to a specific ethnic or dialect group had to be changed. Archbishop Olçomendy also wanted these new churches to reach out to non-Catholics in their community.
From 1949, after the communist takeover of China, Catholic missionaries were expelled by the communist government and many others also left on their own accord for fear of persecution. Some of these missionaries came to Singapore, where they settled. Throughout his term, Archbishop Olçomendy brought in a number of religious orders into Singapore such as the Marist Brothers and Franciscan Missionaries of Mary. In 1958, he sought the assistance of the Congregation of the Sacred Hearts of Jesus and Mary (SS.CC), to build and run a church in the Queenstown area (this was to be the Church of the Blessed Sacrament) and minister to the Catholics who lived there.
Archbishop Olçomendy tendered his resignation in 1976, having reached the age of 75, in accordance with Church laws. After retirement, he lived in Bethany House, a residence he had established to house aged and sick priests. He passed away on 4 July 1977. Upon his death, then-Prime Minister Mr Lee Kuan Yew sent his condolences and thanks for Archbishop Olçomendy’s service and contribution.