Throughout the cycles of war and peace of the last decades, the United Nations has played different roles in Angola. Its political involvement started in the late 1980s, when the Security Council agreed to oversee the independence of Namibia – since 1915 illegally occupied by South Africa – which the New York Accords of December 1988 linked to the withdrawal of Cuban troops stationed in Angola. In the second part of the 1990s, as its peacemaking and peacekeeping roles became increasingly compromised, the UN was limited to humanitarian relief operations and the promotion of human rights.

After many years of deadlock, a tripartite agreement between Angola, Cuba, and South Africa was signed under the auspices of the UN in New York on 22 December 1988, leading to the withdrawal of some 50,000 Cuban troops from Angola and the independence of Namibia, both to be supervised by the UN. Security Council Resolution 626 established the United Nations Angola Verification Mission (UNAVEM I) comprising 70 military observers and 20 civilian officials from ten countries. UNAVEM I was brought to an end with the signing of the Bicesse Accords by the Angolan government and UNITA in May 1991, brokered without UN participation by a Troika of 'observers' consisting of the United States, Russia and Portugal.

Following the Bicesse Accords, UN Security Council Resolution 696 established a second Angola mission, UNAVEM II, on 30 May. Its duty was to observe and verify the disarmament process and support the creation of a new single national army. It also oversaw de-mining, provided humanitarian aid and facilitated the extension of state authority to the whole of Angola's territory. UNAVEM II was staffed with 350 unarmed military observers, 90 unarmed police observers (later increased to 126) and 100 electoral observers (increased to 400 during the elections period). The initial budget was US$132.3 million, later increased by $18.8 million in recognition of its election duties. The UNAVEM II operation in Angola was meant to build on the success of UN involvement in Namibia and elsewhere. However, whereas the UN role in Namibia involved organising the elections, UNAVEM II's role was merely to observe and verify them. Whereas in the smaller and less devastated Namibia the UN had mounted a full-scale operation involving more than 6,000 personnel, the Angola mission was undertaken in a country affected by 16 years of civil war, wrecked infrastructure, and buttressed by two large and mutually suspicious armies.

In effect, the UN's mission, intended to be a small and manageable operation vaguely defined as verification and monitoring, was neither peacebuilding, peacemaking, peacekeeping nor peace enforcement. UN Special Representative Margaret Anstee argued that "the countries most closely concerned with Angola genuinely wanted peace to be restored, but they wanted a 'quick fix', particularly the two superpowers, the main protagonists of the Cold War. ... The result was an agreement flawed from the start, and a marginal role for the UN that was doomed to be ineffectual." Anstee concluded that the UN should never again accept a role in the implementation of a peace accord unless it had been involved in the negotiations of its terms and mandate.

The UN also sought to use Angola as a case study in low-cost post-conflict management, building on its success in Namibia (which in fact benefited from a much higher budget of US$430 million). When Security Council Resolution 747 expanded UNAVEM's mandate and authorised the election budget of US$18.8m, Margaret Anstee famously described her mandate in Angola as like "flying a 747 with only enough fuel for a DC3".

The UN mission declared the September 1992 elections generally 'free and fair', a verdict agreed by the US, EU, South Africa and other international observers. Yet with UNITA disputing the results, within weeks of the elections Angola returned to war. Anstee's attempts to negotiate a ceasefire failed and the Security Council responded by reducing and then fully withdrawing all UNAVEM military personnel. Many Angolans felt disenchanted and blamed the UN for the failure of this transition period, believing that it had been in UNAVEM's power to intervene. In fact, both the government and UNITA publicly denounced each other's failure to comply with the Bicesse Accords by blaming the UN. As British researcher Alex Vines noted, "in September 1992 the government transferred special forces to Malanje under orders to encourage anti–UN slogans during the day and firing gunshots at night. Most of the shots were exchanges between UNITA and MPLA supporters but some were directed towards the UN compound. If the MPLA fared badly in the elections it intended to blame the UN for helping UNITA". The Troika countries, which had been such key players in the Bicesse Accords, were spared any blame.

Two years of war followed before a new peace agreement was reached. Rounds of talks in Namibe province in November 1992, in Addis Ababa in January 1993 and in Abidjan in April-May 1993 all failed. At Namibe both sides agreed to fully implement the Bicesse Accords but the deal and all subsequent attempts at peace talks collapsed, arguably because UNITA sought power at any cost. Both parties were willing to talk only when the balance of power was out of their favour. As Anstee noted, "Angola is on a tragic seesaw. When one side is up they don't want to talk and when the other is up, they don't want to talk." The Security Council's lack of interest was also to blame. With attention focused on Bosnia-Herzegovina, it refused to send 1,000 Blue Helmets demanded by UNITA as a precondition for signing the Abidjan protocol – leaving Anstee as a mediator with empty hands.

In 1993 the UNITA leadership demanded that the UN Special Representative be replaced, implying Anstee was pro-government. Anstee, who had asked to be relieved of her Angolan duties at the end of 1992, was kept on because the UN did not want to appear to be dictated to by UNITA. She departed after the failed Abidjan talks and was replaced by former Malian Foreign Minister Alioune Blondin Beye, who was optimistic about brokering a peace deal. Backed by some African leaders and the Troika of observers and after arduous shuttle diplomacy, he succeeded in bringing the government and UNITA together for preliminary talks in Lusaka in June and November 1993. The US Special Envoy Paul Hare praised Beye's diplomatic experience, intelligence, unflagging energy and tenacity, his willingness to enforce discipline, and the team spirit he instilled amongst the Troika observers. Coupled with the immense military pressure on UNITA, Beye's approach led the parties to finally put pen to paper. The Lusaka Protocol was signed on 20 November 1994.

Beye and Anstee had rather different approaches to their mission. Moreover, unlike the Bicesse Accords, the Lusaka Protocol was negotiated and facilitated by the UN with the support of the Troika. With only limited resources and a weak mandate, Anstee had been left with the task that the Bicesse Accords had failed to address, namely to build confidence amongst the warring parties. Beye picked up where she left off, building on the May 1992 Abidjan talks and backed by an expanded mandate and more resources. He misconceived the process of confidence building, however, by failing to create opportunities for key players to find common ground. Unlike his predecessor, who sought direct involvement from the leadership of the warring parties whenever there was a stalemate in the negotiations, Beye was more inclined to engage regional leaders to lean on and persuade the protagonists instead of directly engaging them himself. Beye's failure to create common ground for the key players was underlined by Savimbi's refusal to attend the signing ceremony: "Mr Beye, he disappointed me. It was not his place to say that I did not come to Lusaka for the signature of the agreement on 20 November because I was 'a beaten man' or because I did not want to be humiliated. He talks too much! Now he wants to come here to meet with me. It is not longer worth the trouble. It is over. I do not want to talk to him any longer". Beye's tragic death in an air crash in June 1998 prematurely ended his involvement in the Angolan peace process.

Under the Lusaka Protocol both sides were to conclude the 1992 election process under UN supervision, with the Special Representative chairing the Joint Commission to oversee the implementation of the protocol, including a ceasefire, quartering of UNITA soldiers and disarmament. The power-sharing clause also provided assurances to the UN that both parties had the political will to restore peace. They agreed to obey all previous Security Council resolutions and UNAVEM III was established to have a presence of 7,000 Blue Helmets (about ten times the size of the UNAVEM II force in 1992). Nevertheless, most Angolans saw UNAVEM III and its smaller successor, the United Nations Observer Mission in Angola (MONUA), as useless, unable as it was to deal with UNITA's relentless pursuit of power or to halt transgressions of the accords, including re-armament, by both sides.

When UNAVEM III's mandate expired in June 1997, MONUA was created, with a heavily reduced military component of only 1,500 troops. The rapidly deteriorating military situation across Angola undermined MONUA's efforts to prevent open conflict and the shooting down of two UN planes by UNITA in December 1998 and January 1999 quickened its slide into irrelevance. Both the government and UNITA demanded UN withdrawal. Attempts to re-start dialogue with Savimbi by Beye's successor Issa Diallo were blocked by the government, which refused to provide security guarantees and threatened to end all contact with him. In February 1999 the Angolan government called for the closure of MONUA and the Special Representative's office was consequently moved from Luanda to New York. A 30 person United Nations Office in Angola (UNOA) remained, mandated to "liase with political and civilian authorities with the view to exploring measures for restoring peace". Yet Diallo failed to persuade the government to enter into negotiations because this time the balance of power was in its favour, and it was determined to pursue its 'peace through war' policy. Angola's oil wealth strengthened the government's ability to raise funds, ensuring that UNOA was restricted to humanitarian issues and institutional capacity building.

Following the Luena Memorandum of April 2002, Security Council Resolution 1433 of August 2002 established the United Nations Mission in Angola (UNMA) to replace UNOA. UNMA's was mandated to chair the reinstated Joint Military Commission, to provide 30 military observers to monitor the quartering areas as guarantors of the agreement, and to coordinate the humanitarian efforts of all other UN agencies.

However, the UN's past failures undermined its ability to play a major role, as did the fact that the agreement was signed between a winner (the government) and a loser (UNITA). The victorious government was able to restrict UNMA's role in the post-Luena period to merely blessing the agreement, and as a means to signal its commitment to the Lusaka Protocol to UNITA. Indeed, quartering areas were managed and controlled solely by UNITA and the FAA without the presence of the 30 observers stipulated under the Luena Memorandum. Ibrahim Gambari, Under Secretary for African Affairs, raised concerns at the official signing ceremony regarding the validity of the Amnesty Law passed by the Angolan national assembly, on the grounds that the UN does not recognise any amnesty as applicable to genocide, crimes against humanity and war crimes.

From 1993 to 1997 the UN adopted a series of sanctions against UNITA. Among these were a ban on military equipment and petroleum products (Resolution 864); the blocking of foreign travel by its officials, and closing of its offices abroad (Resolution 1127); restrictions on air and sea travel to UNITA zones; freezing of UNITA bank accounts, and the prohibition of direct and indirect export of illegal diamonds (Resolution 1173). A Sanctions Committee was established but remained largely ineffective against UNITA's constant violations and the complicity of many countries, companies and individual traders. Indeed it was under the sanctions regime that UNITA's diamond sales netted some US$1.72 billion between 1994 and 1998. Its officials travelled unimpeded especially in Africa and continued to be vocal throughout the world through their 'unofficial' representatives.

Soon after his appointment in 1999, the Sanctions Committee Chairman, Canadian Ambassador Robert Fowler, described the sanctions against UNITA as traffic rules that nobody enforced: "People drove where they wanted and parked all over the place. It was a complete disaster". He recommended the establishment of a panel of experts "to trace violations in arms trafficking, oil supplies and the diamond trade, as well as the movement of UNITA funds abroad". In May 1999 the Security Council established two expert panels to carry out those investigations (Resolution 1237) and Fowler presented their findings in March 2000. His strategy of naming and shaming a series of 'sanctions-busters', both countries and individuals, had never been seen before in the UN's history and provoked quite an uproar among member states accused of helping UNITA to contravene the sanctions regime. The report identified government officials of those countries and named five serving or former heads of state as personally implicated in sanctions busting. The Fowler report led to an improved sanctions-monitoring mechanism and UNITA claims that sanctions contributed towards its defeat in the last phase of the war. They were only fully lifted in late 2002.

Besides its political role in Angola, the UN and its agencies have been active in humanitarian affairs. The UN Humanitarian Assistance Coordination Unit (UCAH) was established by the Department for Humanitarian Affairs (DHA) in April 1993 to coordinate all UN humanitarian operations, including, at the time, the repatriation of 300,000 refugees; assistance for some 800,000 internally displaced persons; provision of emergency food and medical assistance; and the quartering of soldiers

Unlike the UN verification and monitoring missions that were under the same command, UCAH played a positive role at a time when there was no sign of an imminent ceasefire and humanitarian conditions were deteriorating. It succeeded in reaching those in need, initially in Kuito and Huambo and later in other parts of the country. UCAH's success was down to its purely humanitarian mission. However, it was slowly phased out under the Lusaka Protocol and when the country returned to war, UNITA and the government refused to open new humanitarian corridors and provide security for humanitarian personnel. This resulted in a worsening of the humanitarian crisis, which had already reached catastrophic levels in mid-1993. After UCAH's closure, the DHA's successor, the Office for the Coordination of Humanitarian Affairs (OCHA), continued work in Angola until June 2004, coordinating relief to quartered troops and their families, displaced persons and returnees.

The UN's activities in Angola were compromised from the outset. Margaret Anstee noted that, "as the Cambodian experience demonstrated, even with the strongest mandate, and resources to match, it is virtually impossible for a peacekeeping force to demobilise and disarm fully a wily guerrilla army in a vast country with porous frontiers." As a consequence, the UN's role became increasingly restricted to humanitarian operations and a small human rights division. Its shortcomings offer the organisation many salutary lessons.