Original: The Gallipoli Campaign, also known as the Dardanelles Campaign or the Battle of Gallipoli, took place at the peninsula of Gallipoli in the Ottoman Empire between 25 April 1915 and 9 January 1916, during the First World War.
Simplified: The Gallipoli Campaign was an Allied attack on the Gallipoli peninsula during World War I/O. The campaign took place between April 25, 1915 and January 9, 1916.