Here I will 一覧 off all the ポケモン Ash caught within the first 16 seasons of the anime, what season he caught them, what episode he caught them, where he caught them, and their original trainers (if they had a trainer before Ash). Here are the first 20.
Kanto (Original Series)
1. ピカチュウ (episode 1- Pokémon- I Choose You!)
Pikachu was Ash's starter ポケモン that he received from Professor Oak. He received ピカチュウ because he woke up late on the 日 he was supposed to start his ポケモン training. ピカチュウ didn't like Ash AT ALL when Ash first got him, and was very disobedient, refusing to help...