It was founded by Don Stephen Senanayake, who later became the first Prime Minister of Ceylon (The country gained independence from the United Kingdom during this term of office), in 1946 by the amalgamation of Ceylon National Congress and the Sinhala Maha Sabha, and the adhesion of other political elements willing to support its policy. The approval of the Soulbury Constitution, which issued its report in 1945, enabled the party to be formed. Thus, this new party was established with an immense island-wide appeal. The first meeting to form the UNP took place on 4th June, 1946 at the House of Representatives, where the draft constitution of the party was compiled.

The party predominantly represented the business community, landed gentry and included people from all ethnolinguistic groups. Its members were bound by the common principles of Ceylonese nationalism, parliamentary democracy, and continuous economic progress through free enterprise. However, D.S Senanayake embraced certain populist policies as well, which enhanced the party to be trusted on a grassroot level. As a result of such policies, many people without lands were relocated to fertile dry zones and new agricultural colonies were built which resulted in Sri Lanka agricultural production. In late 1947, when the party won the country's first general election, the UNP attempted to establish an anti communist, intercommunal parliamentary form of government. The strength of the United National party rejuvenated the national political movement and sought to build a stronger, safer, and better Sri Lanka.

Today, the party has certainly flourished and lived up to its strong grassroots, while upholding the proud traditions of the UNP; the core principles of the movement have not changed. The United National Party constantly strived to stand up for sovereignty, strong national defense, national unity, free enterprise, and individual achievement, empowering all citizens, regardless of background, to achieve their dreams in a safe, healthy, and prosperous country.

Ranil Wickramasinghe

Hon. Ranil Wickremesinghe has been sworn in as the Prime Minister of Sri Lanka on five occasions. He was first appointed as PM from 1993 – 1994 after the assassination of President Ranasinghe Premadasa. Subsequently, from 2001 to 2004 he was elected as the Prime Minister to lead the United National Front Government during the presidency of President Chandrika Bandaranayake. In January 2015, he was appointed as the Prime Minister of the coalition government on the election of President Maithripala Sirisena. His appointment was sanctioned by the Sri Lankan people at the general election of August 2015. Once again, in December 2018, President Sirisena was compelled to appoint him as PM after having illegally dismissed him in October 2018. In November 2019, after the defeat of the UNP presidential candidate, he resigned from his position of Prime Minister. He is the Leader of the United National Party (UNP), Sri Lanka’s largest political party in the Sri Lankan Parliament. He is currently Sri Lanka's senior-most and longest-serving statesman who has continuously served the country as a member of Parliament since 1977.