Fr. Theodore Joset (Chinese: 若瑟神父, 7 October 1804 – 5 August 1842) was a Swiss priest and the first Prefect Apostolic of Hong Kong.
Fr. Josef was born in Courfaivre, Switzerland in 1804. He was ordained as a diocesan priest at Fribourg in 1831 and subsequently spent two years at Saignelégier. He was then appointed as the representative of the Sacred Congregation for the Propagation of the Faith in the Portuguese colony of Macau. He departed for China on 13 August 1833, and arrived 15 months later in Macau on 15 November 1834.
Fr. Josef was to assist Raphael Umpierres, the Procurator of the mission at Macau, and then succeeded the position in 1835. On 17 Dec 1839, he was also appointed consul general to Charles Albert, King of Sardinia.
The need of pastoral care in Hong Kong had come to the attention of Fr. Josef during the First Opium War. The British troops stationing in Hong Kong, many of them were Irish and Catholic, had no army chaplains, and only had Macau to look to for religious support. Given the alarming rate of illness and death among British soldiers there, Fr. Josef realized that the services of Catholic priests had become an urgent requirement in Hong Kong.
Fr. Joset then wrote to Rome from Macau and urged the Church to recognize Hong Kong's situation and the need to begin a mission there. Consequently, Pope Gregory XVI decreed to create an Apostolic Prefecture that would include "Hong Kong with the surrounding six leagues," and would be independent from the Macau Diocese, on 22 April 1841. This was only 3 months after the British first hoisted their flag in Hong Kong and well before the signing of Treaty of Nanking, which would formally cede Hong Kong to Britain, in August 1842. Fr. Joset was appointed as Hong Kong's first Prefect Apostolic.