The vast majority of countries do not take the definite article unless they are qualified by an adjective or adjectival phrase:

1. Voy a España

2. I'm going to Spain

3. Es de México

4. He's from Mexico

but

1. en la Italia de hace cincuenta años

2. in the Italy of fifty years ago

3. en el Chile contemporáneo

4. in contemporary Chile

However, there are a number of countries, both masculine and feminine, which may be preceded by the definite article. They are indicated in Chapter 10 as follows: (el) Japón, (los) Estados Unidos, (la) Argentina. Generally speaking, the use of the article is more typical of the written registers. One or two countries, notably El Salvador, have a definite article as part of their name, and it must always be used. As with names of towns (eg El Ferrol) where the article forms an integral part of the name, the article does not combine with de or a in very formal usage, eg:

1. en el norte de (la (R2–3)) Argentina

2. in the north of Argentina

3. el Primer Ministro de(l R2–3) Japón

4. the Prime Minister of Japan

5. la capital de El (R3) / del (R1–2) Salvador

6. the capital of El Salvador