The International Bank for Reconstruction and Development (IBRD) is an international financial institution that offers loans to middle-income developing countries. The IBRD is the first of five member institutions that compose the World Bank Group, and is headquartered in Washington, D.C. in the United States. It was established in 1944 with the mission of financing the reconstruction of European nations devastated by World War II. The IBRD and its concessional lending arm, the International Development Association, are collectively known as the World Bank as they share the same leadership and staff.

Early in the Second World War, John Maynard Keynes of the British Treasury and Harry Dexter White of the United States Treasury Department independently began to develop ideas about the financial order of the postwar world. (See below on Keynes's proposal for an International Clearing Union.) After negotiation between officials of the United States and United Kingdom, and consultation with some other Allies, a "Joint Statement by Experts on the Establishment of an International Monetary Fund," was published simultaneously in a number of Allied countries on April 21, 1944. On May 25, 1944, the U.S. government invited the Allied countries to send representatives to an international monetary conference, "for the purpose of formulating definite proposals for an International Monetary Fund and possibly a Bank for Reconstruction and Development." (The word "International" was only added to the Bank's title late in the Bretton Woods Conference.) The United States also invited a smaller group of countries to send experts to a preliminary conference in Atlantic City, New Jersey, to develop draft proposals for the Bretton Woods conference. The Atlantic City conference was held from June 15–30, 1944.

Eugene Meyer served as Chairman of the Federal Reserve from 1930 to 1933 and was the first President of the World Bank Group.

After WWII, John J. McCloy served as the president of the World Bank.

The first country to receive a World Bank loan was France. The Bank's president at the time, John McCloy, chose France over two other applicants, Poland and Chile. The loan was for US$250 million, half the amount requested, and it came with strict conditions. France had to agree to produce a balanced budget and give priority of debt repayment to the World Bank over other governments.

Eugene "Gene" Robert Black Sr. was President of the World Bank from 1949 to 1963.

The World Bank Institute (WBI) was a "global connector of knowledge, learning and innovation for poverty reduction". It aimed to inspire change agents and prepare them with essential tools that can help achieve development results. WBI had four major strategies to approach development problems: innovation for development, knowledge exchange, leadership and coalition building, and structured learning. World Bank Institute (WBI) was formerly known as Economic Development Institute (EDI), established on 11 March 1955 with the support of the Rockefeller and Ford Foundations.

The International Finance Corporation (IFC) is an international financial institution that offers investment, advisory, and asset-management services to encourage private-sector development in less developed countries. The IFC is a member of the World Bank Group and is headquartered in Washington, D.C. in the United States. It was established in 1956, as the private-sector arm of the World Bank Group, to advance economic development by investing in for-profit and commercial projects for poverty reduction and promoting development.

The International Development Association (IDA) is an international financial institution which offers concessional loans and grants to the world's poorest developing countries. The IDA is a member of the World Bank Group and is headquartered in Washington, D.C. in the United States. It was established in 1960 to complement the existing International Bank for Reconstruction and Development by lending to developing countries which suffer from the lowest gross national income, from troubled creditworthiness, or from the lowest per capita income.

George David Woods served as President of the World Bank from January 1963 until March 1968.

The International Centre for Settlement of Investment Disputes (ICSID) is an international arbitration institution established in 1966 for legal dispute resolution and conciliation between international investors. The ICSID is part of and funded by the World Bank Group, headquartered in Washington, D.C., in the United States. It is an autonomous, multilateral specialized institution to encourage international flow of investment and mitigate non-commercial risks by a treaty drafted by the International Bank for Reconstruction and Development's executive directors and signed by member countries. As of May 2016, 153 contracting member states agreed to enforce and uphold arbitral awards in accordance with the ICSID Convention.

Robert McNamara became President of the World Bank.

From 1974 to 1980 the bank concentrated on meeting the basic needs of people in the developing world. The size and number of loans to borrowers was greatly increased as loan targets expanded from infrastructure into social services and other sectors.

From 1976 to 1980 developing world debt rose at an average annual rate of 20%.

During the 1980s the bank emphasized lending to service Third-World debt, and structural adjustment policies designed to streamline the economies of developing nations. UNICEF reported in the late 1980s that the structural adjustment programs of the World Bank had been responsible for "reduced health, nutritional and educational levels for tens of millions of children in Asia, Latin America, and Africa".

In 1980 the World Bank Administrative Tribunal was established to decide on disputes between the World Bank Group and its staff where allegation of non-observance of contracts of employment or terms of appointment had not been honored.

Alden Winship "Tom" Clausen was President of the World Bank from 1981 to 1986.

Barber Benjamin Conable Jr. was former President of the World Bank Group.

The Multilateral Investment Guarantee Agency (MIGA) is an international financial institution which offers political risk insurance and credit enhancement guarantees. These guarantees help investors protect foreign direct investments against political and non-commercial risks in developing countries. MIGA is a member of the World Bank Group and is headquartered in Washington, D.C. in the United States. MIGA was established in 1988 as an investment insurance facility to encourage confident investment in developing countries. MIGA is owned and governed by its member states, but has its own executive leadership and staff which carry out its daily operations. Its shareholders are member governments that provide paid-in capital and have the right to vote on its matters. It insures long-term debt and equity investments as well as other assets and contracts with long-term periods. The agency is assessed by the World Bank's Independent Evaluation Group each year.

Beginning in 1989, in response to harsh criticism from many groups, the bank began including environmental groups and NGOs in its loans to mitigate the past effects of its development policies that had prompted the criticism.

It also formed an implementing agency, in accordance with the Montreal Protocols, to stop ozone-depletion damage to the Earth's atmosphere by phasing out the use of 95% of ozone-depleting chemicals, with a target date of 2015. Since then, in accordance with its so-called "Six Strategic Themes", the bank has put various additional policies into effect to preserve the environment while promoting development. For example, in 1991 the bank announced that to protect against deforestation, especially in the Amazon, it would not finance any commercial logging or infrastructure projects that harm the environment.

Lewis Thompson Preston was President of the World Bank from September 1991 until his death in May 1995.

Sir James David Wolfensohn served as the ninth president of the World Bank Group (1995–2005).

In order to promote global public goods, the World Bank tries to control communicable disease such as malaria, delivering vaccines to several parts of the world and joining combat forces. In 2000 the bank announced a "war on AIDS" and in 2011 the Bank joined the Stop Tuberculosis Partnership.

Eradicate Extreme Poverty and Hunger: From 1990 through 2004 the proportion of people living in extreme poverty fell from almost a third to less than a fifth. Although results vary widely within regions and countries, the trend indicates that the world as a whole can meet the goal of halving the percentage of people living in poverty. Africa's poverty, however, is expected to rise, and most of the 36 countries where 90% of the world's undernourished children live are in Africa. Less than a quarter of countries are on track for achieving the goal of halving under-nutrition.

Achieve Universal Primary Education: The percentage of children in school in developing countries increased from 80% in 1991 to 88% in 2005. Still, about 72 million children of primary school age, 57% of them girls, were not being educated as of 2005.

Reduce Child Mortality: There is some improvement in survival rates globally; accelerated improvements are needed most urgently in South Asia and Sub-Saharan Africa. An estimated 10 million-plus children under five died in 2005; most of their deaths were from preventable causes.

Paul Dundes Wolfowitz served as the 10th President of the World Bank.

Robert Bruce Zoellick was the eleventh president of the World Bank, a position he held from July 1, 2007, to June 30, 2012.

Forty-five countries pledged US$25.1 billion in "aid for the world's poorest countries", aid that goes to the World Bank International Development Association (IDA), which distributes the loans to eighty poorer countries. While wealthier nations sometimes fund their own aid projects, including those for diseases, and although IDA is the recipient of criticism, Robert B. Zoellick, the former president of the World Bank, said when the loans were announced on 15 December 2007, that IDA money "is the core funding that the poorest developing countries rely on".

In 2010 voting powers at the World Bank were revised to increase the voice of developing countries, notably China. The countries with most voting power are now the United States (15.85%), Japan (6.84%), China (4.42%), Germany (4.00%), the United Kingdom (3.75%), France (3.75%), India (2.91%), Russia (2.77%), Saudi Arabia (2.77%) and Italy (2.64%). Under the changes, known as 'Voice Reform – Phase 2', countries other than China that saw significant gains included South Korea, Turkey, Mexico, Singapore, Greece, Brazil, India, and Spain. Most developed countries' voting power was reduced, along with a few developing countries such as Nigeria. The voting powers of the United States, Russia and Saudi Arabia were unchanged.

To make sure that World Bank-financed operations do not compromise these goals but instead add to their realisation, environmental, social and legal safeguards were defined. However, these safeguards have not been implemented entirely yet. At the World Bank's annual meeting in Tokyo 2012 a review of these safeguards has been initiated, which was welcomed by several civil society organisations.

Traditionally, based on a tacit understanding between the United States and Europe, the president of the World Bank has always been selected from candidates nominated by the United States. In 2012, for the first time, two non-US citizens were nominated.

On 23 March 2012, U.S. President Barack Obama announced that the United States would nominate Jim Yong Kim as the next president of the Bank.

Jim Yong Kim was elected on 27 April 2012 and re-elected for a second five-year term in 2017. He announced that he will resign effective 1 February 2019.

Various developments had brought the Millennium Development Goals targets for 2015 within reach in some cases. For the goals to be realized, six criteria must be met: stronger and more inclusive growth in Africa and fragile states, more effort in health and education, integration of the development and environment agendas, more as well as better aid, movement on trade negotiations, and stronger and more focused support from multilateral institutions like the World Bank.

The World Bank's most recent stated goal is the reduction of poverty. As of November 2018, the largest recipients of world bank loans were India ($859 million in 2018) and China ($370 million in 2018), through loans from IBRD.

Kristalina Georgieva was the Chief Executive of the World Bank Group from 2017 to 2019 and served as Acting President of the World Bank Group from 1 February 2019 to 8 April 2019 following the resignation of Jim Yong Kim.

David Malpass was elected President of the World Bank on April 4, 2019.

The World Bank has been assigned temporary management responsibility of the Clean Technology Fund (CTF), focused on making renewable energy cost-competitive with coal-fired power as quickly as possible, but this may not continue after UN's Copenhagen climate change conference in December 2009, because of the Bank's continued investment in coal-fired power plants.

Amid the global fight with the COVID-19 pandemic, in September 2020 the World Bank announced a $12 billion plan to supply "low and middle-income countries" with a vaccine once it is approved. The plan is set to affect over two billion people.