Four countries are conventionally listed as starting with D — Denmark, Djibouti, Dominica and the Dominican Republic — but a fifth, the Democratic Republic of the Congo, also begins with the letter, which is why published lists give the count as either four or five. The disagreement is about filing convention, not about geography.
The Congo that files under D
The Democratic Republic of the Congo is, by any reading of its official name, a D country. It is also the second-largest country in Africa, with something like 110 million people — so whether it counts changes the letter D from a collection of small and mid-sized states into a letter with a giant in it.
Practice is genuinely split. The United Nations member-state list files it under "Democratic Republic of the Congo" and therefore under D. Many atlases and reference works file it under Congo, Democratic Republic of the — which puts it under C, next to its neighbour. The CIA World Factbook uses "Congo, Democratic Republic of the". Alphabetise a list of ISO country names and you get D; alphabetise a list of common short names and you get C.
Behind that lies one of the most renamed territories on earth:
- Congo Free State (1885–1908) — held as the personal property of King Leopold II of Belgium.
- Belgian Congo (1908–1960) — annexed by Belgium after international outcry over Leopold's administration.
- Republic of the Congo / Congo-Léopoldville (1960–1971) — independent, and confusingly sharing a name with its neighbour across the river.
- Zaire (1971–1997) — renamed by Mobutu Sese Seko, along with the river and the currency.
- Democratic Republic of the Congo (1997–present).
So the same country has at different times filed under C, B, R, Z and D. Our guide to the DRC covers the country itself; for the purposes of this list, the honest answer is that it is a D country that most people look for under C.
Denmark: a country of islands and a realm of three parts
- Capital: Copenhagen
- Area: about 43,000 km² for Denmark proper
- Population: roughly 6 million
- Highest point: Møllehøj, about 171 metres
Denmark is the flattest country in this group and one of the flattest in Europe: its highest point would not qualify as a hill in most mountainous countries, and no part of the country is far from the sea. It consists of the Jutland peninsula, which shares Denmark's only land border with Germany, plus more than four hundred named islands, of which several dozen are inhabited. Copenhagen sits on Zealand, the largest, and is connected to Sweden by the Øresund bridge-and-tunnel and to Funen by the Great Belt fixed link — a country whose modern infrastructure story is largely about stitching islands together.
The subtlety with Denmark is what "Denmark" means. The Kingdom of Denmark is a realm of three parts: Denmark proper, the Faroe Islands and Greenland, both of the latter self-governing with their own parliaments and languages. Add Greenland and the kingdom becomes one of the largest territories in the world by area — Greenland alone is over 2.1 million km², making the Kingdom of Denmark bigger than any country in Europe except Russia. Quote Denmark's area as 43,000 km² and you are describing the European part only.
Djibouti: small country, decisive location
- Capital: Djibouti City
- Area: about 23,200 km²
- Population: roughly 1.1 million
- Lowest point: Lake Assal, about 155 metres below sea level
Djibouti occupies the African side of the Bab el-Mandeb strait, the roughly 30-kilometre gap between the Horn of Africa and Yemen through which all Suez Canal traffic must pass. That one fact organises the entire country. Its port handles the overwhelming majority of landlocked Ethiopia's imports and exports, connected by a modern electrified railway to Addis Ababa. It also hosts foreign military bases from several countries, including the only permanent Chinese overseas base and the largest permanent US base in Africa — an unusual concentration for a state of just over a million people.
Physically it is one of the harshest inhabited places on the planet. Lake Assal, in the Afar Depression, is the lowest point in Africa and among the saltiest bodies of water anywhere, saltier than the Dead Sea. The country sits over the Afar triple junction, where three tectonic plates are pulling apart, which is why it has active volcanic terrain and why geologists study it as a place where an ocean basin is beginning to form. Djibouti was French Somaliland until 1967, then the French Territory of the Afars and the Issas, and took its present name at independence in 1977 — making it, like Zambia and Zimbabwe, a letter entry created by decolonisation.
Dominica and the Dominican Republic are not the same place
This is the most common confusion in the letter, and the two countries are genuinely unalike:
- Dominica — a single volcanic island in the Lesser Antilles, about 751 km², population roughly 67,000, capital Roseau. English-speaking, a former British colony, independent since 1978. It is mountainous and heavily forested, with the Morne Trois Pitons national park and the Boiling Lake, a flooded fumarole that is one of the largest of its kind in the world. Almost no beaches of the postcard sort, and correspondingly little mass tourism.
- Dominican Republic — occupies the eastern two-thirds of Hispaniola, about 48,700 km², population roughly 11.4 million, capital Santo Domingo. Spanish-speaking, a former Spanish then briefly Haitian and French territory. Santo Domingo, founded in 1498, is the oldest continuously inhabited European-established city in the Americas and holds the oldest cathedral and university in the hemisphere.
They are roughly 65 times apart in area, speak different languages, and sit several hundred kilometres from one another. What they share is a name derived from the same root — Sunday, dies Dominica, the day Columbus sighted the island in 1493 in Dominica's case. Airlines and postal services confuse them often enough that both countries' tourist boards publish clarifications, and the confusion has real consequences: after Hurricane Maria devastated Dominica in 2017, a significant share of donations and press coverage was misdirected to the Dominican Republic, which the storm had largely spared.
For the record, the correct short forms are Dominica for the island republic and the Dominican Republic — never "Dominican" alone — for the larger state. The demonym for Dominica is Dominican too, which is precisely why the ambiguity survives.
Denmark and Djibouti both guard a gate
The two smallest-by-area members of the letter make an unexpectedly close pair, because both owe their historical importance to sitting beside a strait that shipping cannot avoid.
Denmark controls the Danish straits — the Øresund, the Great Belt and the Little Belt — the only sea routes between the Baltic and the North Sea. For centuries the Danish crown levied the Sound Dues on every vessel passing Kronborg castle at Helsingør, and that revenue was for long periods the single largest item in the royal treasury. The tolls were abolished by international agreement in 1857, but the geography did not change: everything that leaves a Baltic port by sea, including a very large share of Russian oil exports, still passes within sight of Denmark.
Djibouti's position at Bab el-Mandeb is the same arrangement in a hotter climate and a different century. It does not levy tolls, but it monetises the location in two other ways: port fees on Ethiopian trade, which accounts for the great bulk of throughput, and rent on military bases. Both countries are small, both are resource-poor by any conventional measure, and both are wealthier or more strategically significant than their size and endowment would predict — for the same underlying reason.
The contrast is in what each did next. Denmark converted its position into a diversified high-income economy in which shipping is still central — Maersk, one of the world's largest container lines, is Danish — while Djibouti remains dependent on transit revenue from a single neighbour, which is a far more precarious base. A strait guarantees relevance; it does not guarantee prosperity.
Why the count is contested, and what to answer
If someone asks how many countries start with D, the defensible answer is: four in everyday usage, five if you go by official names, because the Democratic Republic of the Congo qualifies and is usually filed elsewhere. That is not pedantry — it is the same category of problem that makes the total number of countries contested, as our guide to how many countries there are in the world explains.
A few other D entities get offered and none is a sovereign state: Dubai is one of the seven emirates of the United Arab Emirates; Delaware and Dakota are American; Dagestan is a Russian republic; Dahomey was the name of Benin until 1975, and is a genuine former D country in the same way Zaire was a former Z one. Set against a crowded letter like B, which carries seventeen states, D is a thin letter whose most interesting feature is the argument about its fifth member.