Simplify the following text for a Grade 9 native English-speaking person.
Original: The 1948 Summer Olympics , officially known as the Games of the XIV Olympiad , were an international multi-sport event which was held in London , United Kingdom .
Simplified: The 1948 Summer Olympics , officially known as the Games of the XIV Olympiad , were held in 1948 at Wembley Stadium in London , England .