If you have spent any time looking at a map of the world, you probably realize that quite a few countries end in the word "land." They include Finland, Iceland, Ireland, the Netherlands, Poland, Switzerland, Thailand, New Zealand, England, Scotland, Somaliland, and Puntland. Generally speaking, country names that end in "land" are preceded by the name of an ethnic group that historically had a presence there. So "England" is the land of the Anglos, Scotland is the land of the Scots, Thailand is the land of the Thais, and Poland is the land of the Poles.
But don't be fooled; the ethnic group after which a country is named is never the only ethnic group historically present in a territory. The earliest people group in the British Isles were not the Anglo Saxons, after whom England is named, but rather the Celts, known as the Britons. The Celts were a diverse group with numerous different tribes that were spread all over the British Isles. The Anglo Saxons were a Germanic group that settled England beginning in the fifth century. Similarly, the Scots were not one large people group that continually inhabited Scotland. The Picts were one of many people groups that lived there, and they all became known collectively as Scots in the Middle Ages.
There are some exceptions to the rule about -land countries being named after ethnic groups. Ireland is not the land of the Ires; there is no ethnic group known as the Ires. In Irish, the word "Ireland" is rendered Eire, a word that refers to a Celtic goddess. So the word "Ireland" literally refers to the land of the goddess Eire. But don't think that Irish people today worship her! While some undoubtedly do, the vast majority of the Irish are Catholic.
Another exception is New Zealand. It was not named after a people group known as the Zeas; the indigenous people of New Zealand are the Maoris. British and Dutch explorers colonized New Zealand, and Dutch cartographers (mapmakers) named the place after the Dutch province of Zeeland. The Netherlands – home of the Dutch – is not named after a group of people but rather after the flatness of the land.
Viking settlers from Scandinavia were the first (that we know of) to arrive on the islands now known as Greenland and Iceland. During the settlement period in Greenland, the island was experiencing a warm spell that caused it to be particularly green the summer it was discovered. Being literal, the Vikings named it Greenland. Their initial experiences in Iceland were less hospitable, though today, the island averages temperatures about 10 degrees Fahrenheit warmer than Greenland. The island was covered in so much ice, and the seas around it so full of it, that the gloomy and disheartened crew named it Iceland. Today, Iceland is a sovereign country, while Greenland is a territory of Denmark.
Additionally, some countries use the word "land" in how they name their countries in the official language, but the translation doesn't carry over into English. An example is Germany, which is known as "Deutschland" in German.
You may not have heard of Somaliland and Puntland, as the international community does not recognize these governorates as sovereign states. They are part of the country of Somalia, and most countries, as well as the United Nations, recognize Somalia as a sovereign state. However, it is a failed state, meaning that its government cannot establish rule over the people. Somaliland and Puntland are two regions that see themselves as autonomous countries and have their own governments, distinct from Somalia's government. Somaliland is the land of the Somalis. On the other hand, the name Puntland refers to a fabled land – Punt – mentioned in ancient Egyptian sources.
There are plenty of other countries that end in "land," but in a non-English version of it. The word "stan" means "land" in the Persian language, and all countries that end in "stan" mean "the land of," usually an ethnic group. Uzbekistan is the land of the Uzbeks, Kazakhstan is the land of the Kazakhs, Afghanistan is the land of the Afghans, Kyrgyzstan is the land of the Kyrgyz, Turkmenistan is the land of the Turkmen, and Tajikistan is the land of the Tajik. But again, don't be fooled by the ethnicity mentioned in the name. These countries are incredibly diverse in terms of people and cultures.
There's also Pakistan, which means "land of peace." If you have ever heard of Hindustan, the reference is to India, the land of the Hindus (incidentally, the word "India" derives from the word "Hindu").
There are plenty of smaller regions that also end in the word "land." They include Newfoundland, an area in Canada; the Rhineland, a city in Germany; Northumberland, a region in England; Maryland, a state in the United States; and Holland in the Netherlands. There are hundreds of locales that use the toponym "land." There are also countries that no longer exist that used the name "land" in the countries' names, such as Swaziland, Wituland, and Togoland, all in Africa.
And don't forget the happiest place on earth, Disney Land, or the place from Peter Pan that both children and adults wish they could go to, Never Land. But of course, those are not countries.