Earlier this month the World Trade Organisation (WTO) announced that it had chosen the Brazilian Roberto Azevedo, 55, as its next director general. In September he will take over from France's Pascal Lamy, who has served two four-year terms.

It is a personal success for this career diplomat, but it is also a victory for Brazil on the international scene. The Brazilian diplomatic corps pulled out all the stops to convince a majority of the 159 member states that their candidate was the right choice. But Azevedo's appointment is also a new departure, this being the first time that a Brazilian has headed one of the key bodies in the postwar Bretton Woods system. The country at last has a seat at the top table.

The vote "shows a global order in transformation", said foreign minister Antonio Patriota, with "emerging markets [showing] leadership".

The selection process took more than four months. Starting with nine declared candidates, it involved three stages, gradually narrowing the field down to two finalists, Mexico's Herminio Blanco and Azevedo. Both undertook to try to restart the Doha round of trade liberalisation, originally launched in 2001 but held up for years by the deep divisions between developed and developing countries.

Azevedo has been Brazil's permanent representative at the WTO since 2008, establishing a reputation as a gifted negotiator and an advocate of multilateralism. He gained the support of 89 countries, according to the Brazilian foreign ministry.

Some sources maintain that all the African countries and a very large majority among poor and developing nations backed Azevedo. Brazil, Russia, India, China and South Africa (Brics) were certainly unanimous in their support, and after Indonesia's Mari Pangestu had been knocked out, at least three more Asian countries switched to the Brazilian candidate.

Brazil's good relations with emerging countries clearly weighed in the balance, whereas Blanco, backed by the United States, Japan and Britain, was seen as an advocate of free-market values. Despite Brussels' call for a united front in favour of the Mexican, divisions among European Union member states sealed the latter's fate.

According to the Brazilian daily Valor, President Dilma Rousseff called her French opposite number François Hollande the week before the vote, who allegedly told her that France had not yet taken a decision "but that it would vote for a name, not a country".

Azevedo joined Brazil's diplomatic service in 1984 and was allocated to the permanent mission in Geneva in 1997. Four years later he helped set up a dispute settlement unit at the foreign ministry. With the election of President Luiz Inácio Lula da Silva in 2003, Brazil started to play a leading role in the WTO, acting as one of the main negotiators alongside the EU, China and the US.

As the head of the Brazilian delegation, he successfully campaigned against subsidies in rich countries, in particular cotton in the US and sugar in the EU. He has taken part in all the ministerial conferences so far in the Doha round.

The main handicap for Azevedo was Rousseff's protectionist policies, with a range of tax incentives and higher customs duty on about 100 imported goods. Addressing the media, he explained that once elected as the WTO head, he would no longer represent a single country. "Brazil's candidacy [will] bring people together, it does not divide them," he asserted.

Azevedo's acid test will probably come in December, barely three months after taking office, with the ninth WTO ministerial conference in Bali. He will need all his talent to avoid further deadlock, at a time when people all over the world are asking what purpose the organisation serves.

• This article appeared in Guardian Weekly, which incorporates material from Le Monde