Some of the casting for the Straw Hats is based on answers Eiichiro Oda gave for where the crew would hail from in the real world, such as Luffy as Brazilian, Zoro as Japanese, Nami as Swedish, Usopp as South African, and Sanji as French.
Eiichirô Oda gifted the five main cast members with custom made shirts to celebrate the casting announcement, featuring illustrations of their characters.
"One Piece" creator Eiichirô Oda worked closely with the directors and writers to ensure the show would be as close to his vision as possible.
The Japanese dub of the show has the original voice actors of One Piece (1999) reprising their original roles: notable examples include Mayumi Tanaka (Luffy), Kazuya Nakai (Zoro), Kappei Yamaguchi (Usopp), Akemi Okamura (Nami), Hiroaki Hirata (Sanji), Shûichi Ikeda (Shanks), Masane Tsukayama (the second Gold Roger), Mika Doi (Coby), Kôichi Nagano (Helmeppo), Youko Matsuoka (Alvida), Shigeru Chiba (Buggy), Jin Domon (Lucky Roux and Merry), Mariko Kôda (Kaya) and Wakana Yamazaki (Nojiko).
Most of the ships were built in Cape Town, where much of the show was filmed, such as Going Merry, Miss Love Duck, Baratie, Red Force, Garps' ship, many more pirate and marine ships in order to use them in filming.