Eritrea ( /ˌɛrɨˈtreɪ.ə/ or /ˌɛrɨˈtriːə/; Ge'ez: ኤርትራ ʾErtrā, Arabic: إرتريا Iritrīyā), officially the State of Eritrea, is a country in the Horn of Africa. Eritrea derives it's name from the Greek word Erethria, meaning 'red land'. The capital is Asmara. It is bordered by Sudan in the west, Ethiopia in the south, and Djibouti in the southeast. The northeast and east of the country has an extensive coastline on the Red Sea, directly across from Saudi Arabia and Yemen. The Dahlak Archipelago and several of the Hanish Islands are part of Eritrea. Eritrea's size is approximately 117,600 km (45,406 sq mi) with an estimated population of 6 million.

Together with northern Somalia, Djibouti, and the Red Sea coast of Sudan, Eritrea is considered the most likely location of the land known to the ancient Egyptians as Punt (or "Ta Netjeru", meaning "God's Land"), whose first mention dates to the 25th century BC. The ancient Puntites were a nation of people that had close relations with Pharaonic Egypt during the times of Pharaoh Sahure and Queen Hatshepsut.

D'mt was a kingdom located in Eritrea and northern Ethiopia that existed during the 8th and 7th centuries BC. With its capital at Yeha, the kingdom developed irrigation schemes, used plows, grew millet, and made iron tools and weapons. After the fall of Dʿmt in the 5th century BC, the plateau came to be dominated by smaller successor kingdoms, until the rise of one of these polities, the Aksumite Kingdom during the first century, which was able to reunite the area.

The history of Eritrea is tied to its strategic position on the Red Sea littoral, with a coastline that extends more than 1,000 km. Many scientists believe that it is from this area that anatomically modern humans first expanded out of Africa. From across the seas came various invaders and colonizers, such as the South Arabians hailing from the present-day Yemen area, as well as the Ottoman Turks, the Portuguese from Goa (India), the Egyptians, the British and, in the 19th century, the Italians. Over the centuries, invaders also came from the neighboring countries in Africa, like Egypt and Sudan to the west and north, as well as Ethiopia to the south. However, present-day Eritrea was largely affected by the Italian colonisers of the 19th century.

In the period following the opening of the Suez canal in 1869, when European powers scrambled for territory in Africa and tried to establish coaling stations for their ships, Italy invaded Ethiopia and occupied Eritrea. On January 1, 1890, Eritrea officially became a colony of Italy. In 1936, it became a province of Italian East Africa (Africa Orientale Italiana), along with Ethiopia and Italian Somaliland. By 1941, Eritrea had about 760,000 inhabitants, including 70,000 Italians. Through the 1941 Battle of Keren, the British expelled the Italians and took over the administration of the country. The British continued to administer the territory under a UN Mandate until 1951, when Eritrea was federated with Ethiopia per UN Resolution 390A(V) under the prompting of the United States adopted in December 1950.

The strategic importance of Eritrea, due to its Red Sea coastline and mineral resources, along with their shared history, was the main cause for the federation with Ethiopia, which in turn led to Eritrea's annexation as Ethiopia's 14th province in 1952. This was the culmination of a gradual process of takeover by the Ethiopian authorities, a process which included a 1959 edict establishing the compulsory teaching of Amharic, the main language of Ethiopia, in all Eritrean schools. The lack of regard for the Eritrean population led to the formation of an independence movement in the early 1960s (1961), which erupted into a 30-year war against successive Ethiopian governments that ended in 1991. Following a UN-supervised referendum in Eritrea (dubbed UNOVER) in which the Eritrean people overwhelmingly voted for independence, Eritrea declared its independence and gained international recognition in 1993.

The de facto predominant languages are Tigrinya and Arabic, both of which belong to the Semitic branch of the Afro-Asiatic family. English is used in the government's international communication and is the language of instruction in all formal education beyond the fifth grade.

Eritrea is a single-party state. Though its constitution, adopted in 1997, stipulates that the state is a presidential republic with a unicameral parliamentary democracy, it has yet to be implemented. In 1998 a border dispute with Ethiopia led to the Eritrean-Ethiopian War. The war resulted in the death of as many as 100,000 Ethiopian and Eritrean soldiers, although specific casualty estimates are varied.

The Eritrean region has traditionally been a nexus for trade throughout the world. Because of this, the influence of diverse cultures can be seen throughout Eritrea. Today the most obvious influences in the capital, Asmara, are those of Italy. Throughout Asmara, there are small cafes serving beverages common in Italy. In Asmara, there is a clear merging of the Italian colonial influence with the traditional Tigrinya lifestyle. In the villages of Eritrea, these changes never took hold. In the cities, before the occupation and during the early years, the import of Bollywood films was commonplace, while Italian and American films were available in the cinemas as well. In the 1980s and since independence, however, American films have become the most common. Vying for market share are films by local producers, who have slowly come into their own. The global broadcast of Eri-TV has brought cultural images to the large Eritrean population in the Diaspora that visits the country every summer. Successful domestic films are produced by government and independent studios with revenue from ticket sales typically covering the production costs.

Traditional Eritrean dress is quite varied, with the women of most lowland ethnicities traditionally dressing in brightly colored clothes, while the Tigrinya traditionally dress in bright white costumes. Of the Muslim ethnicities, only the Arab or Rashaida tribeswomen maintain a tradition of covering their faces.

Football and cycling are the most popular sports in Eritrea. In recent years, Eritrean athletes have also seen increasing success in the international arena.

Eritrea is located in Northeast Africa and is bordered on the northeast and east by the Red Sea, on the south by Ethiopia, and on the northwest by Sudan. It lies between latitudes 12° and 18°N, and longitudes 36° and 44°E.

The country is virtually bisected by one of the world's longest mountain ranges, formed by the processes that formed the Great Rift Valley, with fertile lands to the west, descending to desert in the east. Eritrea, at the southern end of the Red Sea, is the home of the fork in the rift. The Dahlak Archipelago and its fishing grounds are situated off the sandy and arid coastline. The land to the south, in the highlands, is slightly drier and cooler.

The Afar Triangle or Danakil Depression of Eritrea is the probable location of a triple junction where three tectonic plates are pulling away from one another: the Arabian Plate, and the two parts of the African Plate (the Nubian and the Somali plate) splitting along the East African Rift Zone (USGS). The highest point of the country, Emba Soira, is located in the center of Eritrea, at 3,018 meters (9,902 ft) above sea level.

The main cities of the country are the capital city of Asmara and the port town of Asseb in the southeast, as well as the towns of Massawa to the east, and Keren to the north.