The Museum of London is documenting the artefacts found on the site
A 4,000-year-old axe, two World War II helmets and a 19th Century boat have been found on the Olympic Park site.
Archaeologists have examined findings at the 500-acre site as building work continues for the 2012 Games.
Medieval pottery, a Roman coin and four prehistoric skeletons were also uncovered at the east London site.
The Museum of London is documenting the discoveries. Senior archaeologist Kieron Tyler said they revealed a "previously unknown" London.
So far more than 140 trenches have been dug on the site, the Olympic Delivery Authority (ODA) said.
ODA chairman John Armitt said it was "a huge logistical exercise" to analyse the artefacts while keeping the building work on schedule.
Archaeologists said the site was inhabited from the prehistoric period
Mr Tyler said: "As our analysis progresses, an exciting new story is beginning to emerge.
"We now know that the Olympic Park area was settled and utilised continuously from the prehistoric period onwards. These people lived and died here."
The prehistoric skeletons were buried in graves around an area of Iron Age settlement, he said, and the boat was used for hunting wild fowl on the River Lea.
Mr Tyler added: "This new story of the Lea Valley is London before London - a previously unknown London."
The Olympic Park will include an 80,000-seat stadium, a 17,500-seat Aquatics Centre and 3,000-home Athletes' Village, due to be completed by 2011.