In which city was the first Chess Olympiad held?

The first Olympiad was unofficial. For the 1924 Olympics an attempt was made to include chess in the Olympic Games but this failed because of problems with distinguishing between amateur and professional players. While the 1924 Summer Olympics was taking place in Paris, the 1st unofficial Chess Olympiad also took place in Paris. FIDE (The International Chess Federation or World Chess Federation) was formed on Sunday, July 20, 1924, the closing day of the 1st unofficial Chess Olympiad.

FIDE organised the first Official Olympiad in 1927 which took place in London. The Olympiads were occasionally held annually and at irregular intervals until World War II; since 1950 they have been held regularly every two years.