The Battle of Manila (Filipino: Labanan sa Maynila; Japanese: ; Spanish: Batalla de Manila; 3 February 3 March 1945) was a major battle of the Philippine campaign of 194445, during the Second World War. It was fought by forces from both the United States and the Philippines against Japanese troops in Manila, the capital city of the Philippines. The month-long battle, which resulted in the death of over 100,000 civilians and the complete devastation of the city, was the scene of the worst urban fighting in the Pacific theater. Japanese forces committed mass murder against Filipino civilians during the battle and American firepower killed many people. Japanese resistance and American artillery also destroyed much of Manila's architectural and cultural heritage dating back to the city's founding. Manila became one of the most devastated capital cities during the entire war, alongside Berlin and Warsaw. The battle ended the almost three years of Japanese military occupation in the Philippines (19421945). The city's capture was marked as General Douglas MacArthur's key to victory in the campaign of reconquest. To date, it is the last of the many battles fought within Manila's history.

The Commonwealth of the Philippines (Spanish: Commonwealth de Filipinas or Mancomunidad de Filipinas; Tagalog: Kómonwélt ng Pilipinas or Malasariling Pámahalaán ng Pilipinas) was the administrative body that governed the Philippines from 1935 to 1946, aside from a period of exile in the Second World War from 1942 to 1945 when Japan occupied the country. It was established following the Tydings–McDuffie Act to replace the Insular Government, a United States territorial government. The Commonwealth was designed as a transitional administration in preparation for the country's full achievement of independence. Its foreign affairs remained managed by the United States.During its more than a decade of existence, the Commonwealth had a strong executive and a Supreme Court. Its legislature, dominated by the Nacionalista Party, was at first unicameral, but later bicameral. In 1937, the government selected Tagalog – the language of Manila and its surrounding provinces – as the basis of the national language, although it would be many years before its usage became general. Women's suffrage was adopted and the economy recovered to its pre-Depression level before the Japanese occupation in 1942.

In 1946, the Commonwealth ended and the Philippines claimed full sovereignty as provided for in Article XVIII of the 1935 Constitution.