This would be the 7th U.S. Infantry...regular army as opposed to a volunteer organization. I do not know where they were in 1901, but they were operational at that time. If he joined in 1901, he would not actually have served in the Spanish American War, but possibly in the Philippine American War. The Spanish American War ended on December 10, 1898. Government documents would still list him as being in the Spanish American War since any pension he received would have come from the Spanish American War pension fund. A Philippine American War pension fund was never created.