As these historic photos show, the early months of the war meant residents had to quickly train as soldiers before departing for Europe and leaving their loved ones behind.
In our gallery you will also see young evacuees leaving the city and residents of Goodwood Road about to embark on an outing not realising that in two months time the country would be at war. You will also see some of the first areas to be hit by the air raids and the devastation of those bombs.
MORE RETRO PHOTOS: Portsmouth 70 years ago | The oldest places in Portsmouth | Lost Portsmouth shops
Most of the area in Portsmouth destroyed in air raids has now been rebuilt, but the memories of the devastating war still remain.
More photos from this collection can be found on our new Facebook group Portsmouth Retro – you can join here.
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25. The beginning of the Second World War in Portsmouth
Women ambulance volunteers from Royal Portsmouth Hospital in September 1939. The News PP494 Photo: The News archive
26. The beginning of the Second World War in Portsmouth
Sentry on guard at Portsbridge - a solider with bayonet fixed guarding the entrance to Portsmouth at Hilsea in 1939. Photo: The News archive
27. The beginning of the Second World War in Portsmouth
Portsmouth children being evacuated in 1939. The girl on the left is Marjorie Charman nee Watts. Evacuees board buses at George Street, Portsmouth at the beginning of the Second World War. The News PP5415 Photo: The News archive