The Short Version
The claim is well-supported by the Philippines' official historical authority. The National Historical Commission of the Philippines explicitly confirms both the July 15, 1872 establishment date and the naming in honor of King Amadeo I of Spain, corroborated by multiple secondary sources. The only notable caveat is that no underlying Spanish colonial decree has been cited in the available evidence — all sources rely on secondary institutional summaries. This does not materially undermine the claim but prevents full verification from primary documents.