The end of Eta's armed campaign for an independent, socialist Basque homeland comes after 45 years of violence and more than 800 deaths.

Like the IRA, with which it shared an ideology and occasionally swapped weapons, the group's terrorist tactics have been defeated by increasingly efficient security forces and an increasingly hostile public.

Sympathy for the group's aims drained away as Spain returned to democracy following the death of dictator General Francisco Franco in 1975. Its use of terrorism to achieve political ends became wholly unacceptable after the Madrid bombing of March 11, 2004.

Eta, which stands for "Euskadi ta Askatasuna" or "Basque Fatherland and Liberty", was formed in 1959 under Franco, who outlawed the Basque language and forcibly incorporated the region into the rest of Spain following the end of the civil war in 1939.

The mountain country of the Basques, while never entirely free, had for centuries managed to negotiate a measure of independence from French and Spanish rule.

With its logo of an axe encoiled by a snake signifying strength and secrecy, Eta turned quickly to violence, attempting to derail a trainload of Spanish politicians in 1961.

But it was seven years before the group carried out its first political murder, the assassination of Meliton Manzanas, a loathed secret police chief in the Basque city San Sebastian.

Six men were sentenced to death for the shooting, which coincided with the rise of violent leftist groups in Italy, the Middle East and Northern Ireland. The sentences were later commuted to life imprisonment after protests around the world highlighted the abuses suffered by the Basques under Franco's regime.

Eta carried out its most significant assassination in 1973, planting an underground bomb under the parking space of Admiral Luis Carrero Blanco, Franco's Prime Minister and his anointed successor.

Despite being credited with hastening the end of Franco's rule, Eta failed to capitalise on Spain's to democracy during the following decade, instead killing policemen and government officials at an increasing rate.

In 1980, the group was responsible for killing 118 people. Six years later it carried out what remains its deadliest attack - the bombing of a supermarket in Barcelona that claimed 21 lives. It later apologised calling the bombing a "mistake".

During the 1990s, Eta continued to target politicians,once attempting to blow up Jose Maria Anzar, then the leader of the conservative Popular Party. Anzar was saved by his armour-plated car and went on to become Prime Minister.

But the group was being weakened by arrests and raids by Spanish and French police on its hideouts straddling the border. In 1992, Francisco Mugica Garmendia, the head of Eta, was arrested. Ten years later, he was sentenced to 743 years in prison for a bus bombing in 1987. In 1995, Spanish investigators claimed to have broken up a plot to kill King Juan Carlos II.

By 1998, no doubt conscious of the Good Friday Agreement in Northern Ireland, Eta announced it was willing to negotiate with the Spanish Government and declared a ceasefire.

But the truce collapsed when, after a year, only one meeting had been held. Era announced its return to violence in 2000, killing Fernando Buesa, of the Spanish Socialist Workers' Party. The deaths of 13 more politicians followed in the next three years. Eta, increasingly undone by arrests and politically alienated, became the object of massive protests.

The end of Eta was widely predicted after the Madrid bombings of March, 2004. It was initially blamed by the Spanish Government for the deaths of 199 people - an attack subsequently discovered to have been the work of groups associated with al-Qaeda.

Forced to deny responsibility for terrorism for the first time in its history, Eta could not escape the consequences of the extraordinary peace protests that brought more than 11 million people onto the streets of Spain. The protests led to the swift fall of Senor Aznar's government and the withdrawal of Spanish troops from Iraq.

But long-time observers of Eta noted that the group had not lost its taste for violence. In December 2003, it attempted its own attack on Madrid's train system and just a month before the al-Qaeda attack, Spanish police seized more than 500kg of explosives belonging to the group.

For many, the critical blow only came in October 2004, when 21 senior Eta figures, including Mikel Albizu Iriarte, the group's chief since 1992, were arrested and six former operatives called for their colleagues to lay down their arms.

In May 2005, Eta said it would no longer kill politicians, an offer that was widely scorned in Spain but was nonetheless seen as a crucial step towards today's announcement.