On October 12, 1936, President Manuel L. Quezon signed the law making Zamboanga a Chartered City, but it was not until February 26, 1937 that the first officials of Zamboanga City were sworn into office. At the forefront of this group of newly appointed Zamboangueño leaders was Nicasio Siason Valderrrosa, who was to become the first mayor of Zamboanga as a chartered city.
Valderrosa was born on October 11, 1891, in Bacolod, Negros Occidental. His parents were Domingo Valderrosa of Lucban, Quezon, and Lorenza Siason of Bacolod.
Mayor Valderrosa began his public career as a schoolteacher in Bacolod from 1906 to 1908. He was assigned as chief clerk at the Office of the Division Superintendent of Schools in Negros Occidental from 1907 to 1917. His superiors were so impressed with his performance that in 1918, Ñor Nick, as he was fondly called, was appointed to the Provincial Treasury.
Valderrosa came to Zamboanga in 1930 when he was appointed to the position of Secretary and Treasurer for the Province of Zamboanga. He was to hold this position until 1937. This was to be turning point in Valderrosa’s life as this gave him the opportunity to serve as acting provincial governor for the province, which at that time was undergoing a period of transition.
His management skill did not go unnoticed. It helped him capture the appointment as city mayor. Mayor Valderrosa’s term would be a landmark in Zamboanga City’s history as it was the very first civil government under the Commonwealth, a government that would be run by Filipinos. However, the position of mayor at that time was still an appointive one, and the mayor served at the pleasure of the President. In 1939, Mayor Valderrosa on the request of President Quezon, was assigned to the newly created chartered city of Baguio, which was experiencing administrative problems as a fledgling city. President Quezon felt Baguio needed Valderrosa’s administrative hand.
Despite his reluctance to leave Zamboanga, Valderrosa took up the challenge and served as Bagiuo’s mayor until 1944. He would be the second Filipino to hold the position of mayor of that city until the outbreak of World War II. However, immediately after the war, he was designated by the military authorities through the Philippine Civil Authorities Unit (PCAU) as mayor of Baguio again in order to reorganize its government.
After his assignment in Baguio, Ñor Nick came back to Zamboanga and took up residence here until 1948. When Basilan became a separate city from Zamboanga, he was appointed by President Elpidio Quirino as Basilan’s new mayor, a position he held until 1953.
In 1954, Valderrosa retired after 47 years in public service. After retirement he devoted much of his time to farming and the family business.
As mayor of Zamboanga, Baguio and Basilan, Mayor Nicasio Valderrosa left behind a legacy of accomplishments. In Zamboanga City, he was responsible for the transfer of the Moro village from Cawa-Cawa Boulevard to Campo Islam. He was credited with stabilizing the financial problems in Baguio and the establishment of the workmen’s village. It was also in Baguio where he relocated squatters to Aurora Hill and at the same time started the Sto. Tomas waterworks. The Basileños would always cherish the memory of Mayor Valderrosa as the man who was responsible for the road network in the province. It was to his credit that the Isabela Market and Basilan Electric Plant were constructed.
Mayor Valderrosa was not only energetic as public servant but was also equally very active in civic activities. He was responsible for organizing the Boy Scouts of the Philippines local council and was also involved in the National Red Cross and Anti-Tuberculosis Society.