The US Marine Forces Pacific Band
There were up to 45,000 American troops stationed in camps in New Zealand between June 1942 and mid-1944.
Their presence in Wellington contributed to a minor economic boom, especially for dry cleaners, taxi drivers and milk bars.
Inevitably, romantic liaisons developed. About 1500 New Zealand women married American servicemen, prompting Kiwi men to describe them as invading 'bedroom commandos'.
To commemorate the anniversary, the United States Marine Forces Pacific Band will play at Civic Square - not far from where the marines disembarked in 1942 - from 12.30 - 1.15pm on Thursday 14 June. The programme will include a bit of everything, from military music to jazz and rock.
The band also plays tomorrow (Wednesday) at Old St Paul's Cathedral from 5.30pm, and on Thursday at a ceremony on Parliament's forecourt at 5.45pm.
United States Ambassador David Huebner says New Zealanders welcomed the arriving marines with a hospitality and friendship that endures to this day.
"The events will mark 70 years since US forces travelled halfway across the world to help defend the Pacific and New Zealand, our 'friend in need'," says Ambassador Huebner.
The Council's Events Portfolio Leader, Councillor John Morrison, says the significance of the American forces based here during the war is sometimes lost in the stories about fights over local women who married American soldiers and sailors.
"The 'American invasion', as we like to call it, was a friendly invasion and one that we are very thankful for and will never forget."