Portuguese ( português (help·info) or língua portuguesa) is a Romance language that originated from a fusion of the dialect spoken in what is now Galicia and northern Portugal with closely related dialects spoken in territories to the south which had not yet been reconquered by the Christians to the Arabs by the time Portugal was born as a Christian kingdom in the Iberian Peninsula (first half of the 12th century). It is derived from the Latin spoken by the romanized pre-Roman peoples of the Iberian Peninsula (namely the Gallaeci, the Lusitanians, the Celtici and the Conii) around 2000 years ago. It spread worldwide in the 15th and 16th centuries as Portugal established a colonial and commercial empire (1415–1999) that reached from Brazil in the Americas to Goa and other parts of India, Macau in China, Timor (north of Australia) and the five African countries that make up the PALOP lusophone space (Cape Verde, Guiné-Bissau, São Tomé e Príncipe, Angola and Mozambique).

It was used as the exclusive lingua franca on the island of Sri Lanka for almost 350 years. During that time, many creole languages based on Portuguese also appeared around the world, especially in Africa, Asia, and the Caribbean.

Today it is one of the world’s major languages, ranked seventh according to number of native speakers (between 205 and 230 million). It is the language of about half of South America’s population, even though Brazil is the only Portuguese-speaking nation in the Americas. It is also a major lingua franca in Portugal’s former colonial possessions in Africa. It is an official language in nine countries (see the table on the right), also being co-official with Cantonese Chinese in Macau and Tetum in East Timor. There are sizeable communities of Portuguese speakers in various regions of North America, notably in the United States (New Jersey, New England, California and south Florida) and in Ontario, Canada (especially Toronto).

In various aspects, the system of sounds in Portuguese is more similar to the phonologies of Catalan or French than, say, those of Spanish or Italian. Nevertheless, the grammar, structure and vocabulary of the Portuguese and Spanish languages are so similar that phonetic differences do not impede intelligibility between them any significant way. Spanish author Miguel de Cervantes once called Portuguese “the sweet language”,[6] Lope de Vega referred to it as “sweet” [7] while Brazilian writer Olavo Bilac poetically described it as a última flor do Lácio, inculta e bela: “the last flower of Latium, wild and beautiful”. Portuguese is also termed “the language of Camões”, after one of Portugal’s best known literary figures, Luís Vaz de Camões.

Portuguese is also the fourth most learned language in the world, since approximately 28 million students study this language. The obligatory learning of Portuguese is observed in Uruguay, Argentina, Venezuela, Zambia, Congo, Senegal, Namibia, Swaziland, Côte d’Ivoire and South Africa.