From the 1880s to 1914, several thousand Muslims immigrated to the United States from the former territories of the Ottoman Empire and the former Mughal Empire.[12] The Muslim population of the U.S. increased dramatically in the 20th century, with much of the growth driven by a comparatively high birth rate and immigrant communities of mainly Arab and South Asian descent. About 72% of American Muslims are immigrants or "second generation".[13][14]