Harry Potter and the Philosopher's was the first LEGO theme based on Harry Potter and the first of the novels. The sets are based on the movie version rather than the book version. There were 15 set released in all 2001 to 2002
2002 LEGO Sets
2002 was an interesting year for LEGO. While there were a couple of highly collectable sets such as the Star Wars Imperial Star Destroyer (10030-1) and the Pirates Black Seas Barracuda (10040-1) most sets did not see the kind of growth that previous years had experienced. However, the Star Wars theme carried a lot of the collection's weight, it was the year Star Wars celebrated its 25th Anniversary. The Western theme which included the iconic Fort LEGOredo (6762-1) help the overall investiability of 2002. During 2002 LEGO released a number of new themes including the original Spider-man and Island Xtreme Stunts as well as some prominent subthemes including Episode II: Attack of the Clones for Star Wars, Harry Potter and the Chamber of Secrets and Mission Deep Sea under Alpha Team.