Complex sentence: In 1884 (103 of Rattakosin Era), Siamese officials in London and Paris arranged a request to Chulalongkorn, citing the threats from European colonialism were coming and Siam should be reformed like Meiji Japan and Siam should become a constitutional monarchy.
Split into simpler sentences: In 1884 (year 103 of the Rattakosin Era), Siamese officials in London and Paris warned Chulalongkorn of threats from European colonialism. They advised that Siam should be reformed like Meiji Japan and that Siam should become a constitutional monarchy.