I le amataga o taua ma Sepania, na siitia ai o ia i le tulaga o le taʻitaʻiʻau aoao o le au tauofo i le masina o Me 1898. I Cuba i le taimi o le taua, na ia taʻitaʻia ai se tasi o vaega e lua o fitafita tiʻetiʻe solofanua, o se vaega o le Vaega o fitafita tiʻetiʻe solofanua i lalo o le taʻitaʻiga a Major General Joseph Wheeler. O le vaega a Young e aofia ai le Rough Riders a Theodore Roosevelt, o le 1st US Volunteer Cavalry Regiment. Iā Iulai 1898, ina ua manumalo Amerika i le Taua i le Mauga o San Juan
Na avea Young ma ta'ita'i o le vaega a le Wheeler's Cavalry Division ma avea ai o ia ma Major General of volunteers a'o ia ta'ita'ia le vaega lava lea e tasi i Cuba ina ua mae'a le Campaign Santiago o le Spanish-American War. I le tausaga lava lea e tasi, na avea ai Young o se Tausisoifua Taua o le Missouri Commandery of the Military Order of Foreign Wars.