Throughout history, nations have struggled to claim their title as the largest country in the world. This is as true today as in the past. However, as the world has access to more information and people have the ability to travel freely, communicate easily, and purchase, sell, or trade with the click of a computer button, the definition of largest is not as simple as it once was.

There are a lot of different ways to define size including geographic area, population, and economic leverage. We’ve got an overview of ways that various countries currently make it to the top of the list when they are measured by these specific criteria.

Measured by area: Russia

When measured in square kilometers, the largest country on the globe is currently Russia. It is so large that it borders 14 other countries and contains multiple geographic environments. It is worth noting that if someone were to remove seven million square kilometers Russia would retain its place at the top of the list while the seven million square kilometers would take a place in the top ten list of largest countries by area.

The second-largest country in the world is Canada. With almost ten million square kilometers, it includes both extensive coastlines, huge mountains, and access to the Arctic circle. It is followed in size by its continental neighbor the United States which retains much of its 9.8 square mass by access to Alaska. China and Brazil round out the other two nations in the list of top five countries by area. They are, respectively, 9.59 and 8.51 square kilometers each.

How does this compare to the size of empires throughout history? In ancient centuries, Alexander the Great created one of the largest empires known, stretching from Greece to northwest India. In the first century AD, the Roman Empire stretched for 5.7 million square kilometers and included approximately twenty percent of the world’s population. Centuries later, Mongolian leader Genghis Khan kicked off the creation of an empire that ultimately grew to approximately 23 million square kilometers.

Measured by population: China

Population is another frequently-cited way to measure a country’s size. According to the U.S. Census Bureau, China takes the top spot in the world in terms of population. While it is the fourth-largest country by area, as of July 2019, it was listed as having nearly 1.4 billion people despite past policies to help manage population growth. The only other country with more than a billion people is second-place India which as just over 1.3 residents. Together this is a huge percentage of the more than 7.58 billion people estimated to be living throughout the world.

The rest of the countries in the top five world countries in terms of their population fall well below China and India. They include the United States with almost 332 million people, Indonesia with nearly 265 million people, and Pakistan with almost 211 million people. It is worth noting that this top five list is particularly heavy with countries from Asia, where growth has quadrupled overall in the 20th century. Astoundingly, overall Asia retains 30 % of the world’s land area but 60% of its population.

Measured by economic impact: The United States

Though it comes in third on a list of countries measured by square kilometers and population, the United States is at the top of the list when measured by its economy. In 2019, its nominal GDP (Gross Domestic Product) forecast is expected to exceed 21 trillion USD (U.S. Dollars). This is 20 percent of global output. Number two in this category is China which has more than 14 trillion GDP as measured in USD. Well behind both of these leaders is Japan, Germany, and the UK which have GDP output calculated to be approximately 5.2, 4.2 and nearly 3 trillion USD respectively.

A couple of things are worth noting when reviewing a country’s economic impact. China’s story of explosive growth is obvious, with an economy that grew by 35 percent since 1978 when it began a series of economic reforms. Currently, it is a powerhouse that holds substantial weight, though never the number one spot, in terms of landmass, population, and economy. However, many countries making a strong economic impact have neither large areas of land nor booming populations to account for their global contributions.

These current economic rankings aren’t necessarily permanent and may not tell the whole story. According to the International Monetary Fund (IMF), if you adjust the rankings to include a lower standard of living and lower consumer prices (an adjustment known as ranking for purchasing power parity), China passed the U.S. in 2014. The country may pass the U.S. by traditional GDP valuations as soon as 2030.

In contrast: The smallest countries

Just for fun, it can be fun to compare the size, population, and impact of the largest countries in the world with those at the other end of the spectrum. So, how small can countries on our planet get? In terms of landmass, the smallest country in the world is Vatican City with less than a kilometer of area. It consists of .44 square kilometers to be exact. It is followed by Monaco which measures just over 2 square kilometers. With approximately 1,000 people living there, Vatican City also claims the top spot on a list of smallest countries in terms of population.  The island nation of Tuvalu is the second least-populated country measuring just over 11,000 people. In 2019, Tuvalu and Nauru had the least amount of economic impact, measured at 45 and 114 GDP respectively.