The Inian Rebellion of 1857 began as a mutiny of sepoys of British East India Company's army on the 10th of May 1857, in the town of Meerut, and soon erupted into other mutinies and civilian rebellions largely in the upper Gangetic plain and central India, with the major hostilities confined to the region of present-day Uttar Pradesh, Uttarakhand, northern Madhya Pradesh or Saugor and Nerbudda Territories, Delhi, and Gurgaon. The rebellion posed a considerable threat to Company power in that region, and it was contained only with the fall of Gwalior on 20 June 1858. The rebellion is also known as India's First War of Independence, the Great Rebellion, the Indian Mutiny, the Revolt of 1857, and the Sepoy Mutiny.