The territory of the present-day Montenegro was first settled by the Illyrian people in the years before 1 AD. An indulgence in piracy caught the attention of neighbours across the Adriatic - in 9 AD the Romans invaded and annexed the region, calling it Illyricum. The inhabitants became partly romanised, but the decline in Rome's power from the 5th century onwards saw destructive raids from tribes such as the Goths and Avars. In the 6th century, people from the Slavia region on the Baltic coast began to migrate south and eventually settle in the Montenegro region. Many place names from this period still exist. In the 7th century a second wave of migration by Serbs and Croats took place.

By about 650 AD the region had acquired a distinct cultural identity and was called Doclea (Duklja), which later evolved into a semi-independent Dukedom, serving allegiance to the Roman Catholic Byzantine Empire. The Pope recognised Duklja as an independent state in 1077. Also at this time, the name Zeta was first being applied to the principality, after the local river of the same name. Dynastic feuds weakened the defences of Duklja/Zeta and in 1183 the neighbouring Duke of Serbia invaded and forcibly imposed the Orthodox Christian religion on the population. Before long however, Zeta was assuming a degree of autonomy. In 1296 a charter first mentions the name Montenegro as being part of Zeta.

Seizing a favourable opportunity, in 1356 Zeta broke away from Serbian domination and became an independent kingdom. Although frequently threatened by the Ottoman Empire - which soon controlled nearly all of Zeta's neighbours - the Turks never managed to completely subjugate Zeta. Numerous mountain strongholds rendered the task virtually impossible for the Turks. From 1516 the country was officially known as Montenegro.

In 1799 the Ottomans finally recognised the independence of Montenegro. The relative peace that followed allowed many internal reforms to take place, and saw a revival of learning and culture. On 13 July 1878 the Treaty of Berlin saw the Great Powers of Europe formally recognise Montenegro as a sovereign state and confirmed it's territorial gains from the Ottomans during recent wars.

In 1910 Montenegro was proclaimed a Kingdom. Following prior arrangement with Serbia, on 8 October 1912 Montenegro attacked the Ottomans, starting the First Balkan War. An armistice in December 1912 stopped the fighting for a while, but the Second Balkan War followed and was only ended by the Treaty of Bucharest in November 1913.

The start of the First World War saw Montenegro come to the aid of its longtime ally, Serbia. On 6 August 1914 Montenegro declared war on Austro-Hungary. Initial military successes were revered when combined Austrian and German forces invaded and occupied Montenegro in January 1916. The king was forced into exile in France.

In September 1918 Serbian forces liberated Montenegro. A national assembly organised under Serbian supervision declared the king deposed and agreed a union with Serbia. On 1 December 1918 Montenegro was incorporated into the newly formed Kingdom of Serbs, Croats and Slovenes. Montenegro was thus the only country on the winning side in the First World War to lose its independence. The unification was deeply unpopular and on 7 January 1919 (the Orthodox Christmas Day) a national uprising to oppose the change began. A bloody military campaign by Serb forces to suppress the uprising took almost 7 years to complete. Under the centralised, Serbia-dominated government of what became the Kingdom of Yugoslavia in October 1929, Montenegro largely ceased to exist.

In April 1941 Yugoslavia was invaded by the military forces of Germany and its allies, beginning a long hard and eventually successful war of resistance by Yugoslav partisans under the leadership of General Tito. On 29 November 1945 the Federal Republic of Yugoslavia was established, with Montenegro as one of the constituent republics.

Economic and political liberalisation after the death of General Tito in 1980 eventually saw the introduction of multi-party democracy in Montenegro. During the disintegration of Yugoslavia in the early 1990s, Montenegro and Serbia were the only republics to keep the communists in power and vote to remain within the Yugoslav federation. Montenegro initially supported Serbian military resistance to the break-up, but soon backed of as the consequences became clear.

After 1995 Montenegro privatised businesses and pursued a market economy. During the Kosovo War of April 1999, targets in Montenegro were attacked by NATO aircraft. In November 1999 the German Mark was adopted as legal tender alongside the dinar. Relations with the hardline Milosevic government in Belgrade deteriorated throughout 1999 and in December Serbian troops actually occupied Podgorica Airport for a day - underlining it's potential use as a military bridgehead for invasion. The dramatic deposing of Milosevic in October 2000 brought about a significant improvement in relations with Serbia.

In March 2002 the Euro replaced the Mark as the sole legal currency. In the same month, a pact with Serbia was agreed calling for a restructured looser federal government. In February 2003 the new constitution was approved, establishing the state union of 'Serbia and Montenegro'. Despite this, support for full independence continued to grow. On 21 March 2006 a national referendum saw Montenegrins voted narrowly in favour of independence. On 3 June 2006 Montenegro parliament formally declared independence from Serbia. Montenegro now aspires to join the European Union and NATO.