On September 7, 1998, the 15th episode in the first season, Battle Aboard the St. Anne, became the first ever Pokémon episode to be aired on American TV (likely because it was more action-packed), with I Choose You following on September 8.
Oh God. The show’s first ever episode, Pokémon – I Choose You!, is the beginning of the whole Pokémon universe, showing Ash’s first ever meeting with Pikachu.
While I Choose You is the first episode sequentially in the series, it was bizarrely shown second in the US.
On September 7, 1998, the first episode of the Pokémon anime aired in the United States.