The clash between the Moros and the Americans who embraced differing notions of sovereignty eventually led to a war that is known in the annals of American military history as the Moro Campaigns. History books regard this war, together with the Filipino war against the United States from 1899-1902, as the "Spanish-American War." The clash with the Moros was one of America?s most ferocious encounters with a Muslim ummah. For the Moros, the clash between themselves and the Americans was a continuation of their war against foreign invaders that began with the Spaniards.