The Central Powers (German: Mittelmächte; Hungarian: Központi hatalmak; Turkish: İttifak Devletleri or Bağlaşma Devletleri; Bulgarian: Централни сили) were one of the two warring factions in World War I (1914–18), composed of the German Empire, the Austro-Hungarian Empire, the Ottoman Empire, and the Kingdom of Bulgaria. This alignment originated in the Triple Alliance, and fought against the Allied Powers that had formed around the Triple Entente.

The Central Powers consisted of the German Empire, the Austro-Hungarian Empire, the Ottoman Empire, and the Kingdom of Bulgaria. The name "Central Powers" is derived from the location of these countries; all four were located between the Russian Empire in the east and France and the United Kingdom in the west.

The Central Powers were composed of the following nations:

On 7 October 1879, Germany and Austria-Hungary became allies and formed the Dual Alliance. On 20 May 1882, they were joined by the Kingdom of Italy in what was known as the Triple Alliance. This alliance was intended to be limited to defensive purposes only.

World War I (WWI), which was predominantly called the World War or the Great War from its occurrence until 1939 (World War II), and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918. It involved all the world's great powers, which were assembled in two opposing alliances: the Allies (based on the Triple Entente of the United Kingdom, France and Russia) and the Central Powers (originally centred around the Triple Alliance of Germany, Austria-Hungary and Italy; but, as Austria–Hungary had taken the offensive against the agreement, Italy did not enter into the war). These alliances both reorganised (Italy fought for the Allies), and expanded as more nations entered the war. Ultimately more than 70 million military personnel, including 60 million Europeans, were mobilised in one of the largest wars in history. More than 9 million combatants were killed, largely because of enormous increases in lethality of weapons, thanks to new technology, without corresponding improvements in protection or mobility. It was the sixth-deadliest conflict in world history, subsequently paving the way for various political changes such as revolutions in the nations involved.