Seria area was gazetted as municipal area in 1936. The town came under the authority of the Kuala Belait Sanitary Board which also had responsibility for the municipal area of Kuala Belait.
The first landing of the Japanese invasion force during WW2 in Borneo was at Seria where the Left Flank of the "Kawaguchi Brigade" came ashore about 04.40 on the 16th December 1941, nine days after Pearl Harbor.
They were faced with a scene of devastation of the oilfields due to "Operation Denial" carried out by employees of the British Malayan Petroleum Company (now Brunei Shell Petroleum) and the 2nd Battalion, 15th Punjab Regiment, and British Army Royal Engineers. The invasion force continued oil drilling units and restoration of the oilfields began immediately under Sato, Chief Engineer.
Over the next three years the Japanese restored production to nearly pre-war levels, the activity being hectic as other sources of supply to the Japanese war machine were closed off, so much so that most of the oil fuelling the Japanese in the last 6 months of the war came from Seria.
Operation "Ha-Go 2", the Japanese denial exercise commenced on 10 June 1945, the day of the Australian liberation forces landing at Muara. The fires could be seen 100 km out to sea.
When the Australian 9th Division as part of Operation Oboe Six eventually entered Seria on the 29th June, the situation was chaotic, with 38 oil well fires, demolished buildings and wrecked installations.
By the 17th August, when American Fire fighting teams (Patton and son) arrived, 26 of the fires had been put out by oilfield staff assisted by a Detachment of the Australian Royal Engineers. By November, production was restored, albeit stored in temporary tanks, and oil export to Lutong recommenced on the 11th December 1945.
Seria was also one of the centres of a small rebellion against the monarchy on December 8, 1962, which was suppressed by the British Army. This event became known as the Brunei Revolt.
Under the rule of His Majesty the late Sultan Omar Ali Saifuddin, the town blossomed as commercial buildings such as the current shophouses along Jalan Sultan Omar Ali.
SERIA IN THE OLD DAYS
Seria Town in 1950s
Seria Town in the old days