Primate city

A primate city is a city that is the largest in its country, province, state, or region, and disproportionately larger than any others in the urban hierarchy. A primate city distribution is a rank-size distribution that has one very large city with many much smaller cities and towns and no intermediate-sized urban centers, creating a statistical king effect.

The law of the primate city was first proposed by the geographer Mark Jefferson in 1939. He defines a primate city as being "at least twice as large as the next largest city and more than twice as significant." Aside from size and population, a primate city will usually have precedence in all other aspects of its country's society such as economics, politics, culture, and education. Primate cities also serve as targets for the majority of a country or region's internal migration.

In geography, the phenomenon of excessive concentration of population and development of the main city of a country or a region (often to the detriment of other areas) is called urban primacy or urban macrocephaly.

Measurement
Urban primacy can be measured as the share of a country's population that lives in the primate city. Relative primacy indicates the ratio of the primate city's population to that of the second largest in a country or region.

Significance
There is debate as to whether a primate city serves a parasitic or generative function. The presence of a primate city in a country may indicate an imbalance in development—usually a progressive core and a lagging periphery—on which the city depends for labor and other resources. However, the urban structure is not directly dependent on a country's level of economic development.

Many primate cities gain an increasing share of their country's population. This can be due to a reduction in blue-collar population in the hinterlands because of mechanization and automation. Simultaneously, the number of educated employees in white-collar endeavors such as politics, finance, media, and higher education rises. These sectors are clustered predominantly in primate cities where power and wealth are concentrated.

Examples
Some global cities are considered national or regional primate cities. An example of a global city that is also a primate city is Istanbul in Turkey. Istanbul serves as the primate city of Turkey due to the unmatched economic, political, cultural, and educational influence that the city possesses in comparison to other Turkish cities such as the capital Ankara, İzmir, or Bursa. Mexico City, Paris, Cairo, Jakarta, and Seoul have also been described as primate cities of their respective countries. However, not all regions and countries possess a primate city. The United States has never had a primate city on a national level due to the decentralized nature of the country and because the country's second-largest city, Los Angeles, is not far behind the country's largest city, New York City, in either population or GDP. The metropolitan area of New York City has over 19 million residents, while that of Los Angeles has roughly 13 million residents, as of 2022.

Sub-national divisions can also have primate cities. For instance, New York City is New York State's primate city, because its population is 32 times bigger than the state's second-largest city of Buffalo. New York City has 44% of the population and 65% of the GDP of New York State. The city of Anchorage is another U.S. example, with around 40% of the total population of Alaska living within the city's limits. China does not have a primate city at a national level, but several provincial capitals are disproportionately larger than other urban areas in the respective provinces. For example, Henan, Hubei, and Sichuan have provincial capitals (Zhengzhou, Wuhan, and Chengdu, respectively) that are significantly larger than the second-largest cities in those provinces, and each of those provinces has a population similar to that of a large European country. India does not have a primate city, as Delhi is not much larger than Mumbai or Kolkata in terms of population. However, many Indian states, such as Karnataka, West Bengal, Tamil Nadu and Maharashtra, do have primate cities: Bangalore, Kolkata, Chennai, and Mumbai, respectively. Other Indian states, such as Uttar Pradesh and Kerala, do not have any primate cities.

Bangkok, the capital of Thailand, has been called "the most primate city on Earth": in 2000 it was 40 times larger than the second-largest city of that time, Nakhon Ratchasima. As of 2022, Bangkok is nearly nine times larger than Thailand's current second-largest city of Chiang Mai, which has been growing in population and has also had its boundaries expanded to reflect that growth. Taking the concept from his examination of the primate city during the 2010 Thai political protests and applying it to the role that primate cities play if they are national capitals, researcher Jack Fong noted that when primate cities like Bangkok function as national capitals, they are inherently vulnerable to insurrection by the military and the dispossessed. He cites the fact that most primate cities serving as national capitals contain major headquarters for the country. Thus, logistically, it is rather "efficient" to target a national capital that is also a primate city; most of the governing power is contained in that one small area, and so are most of the people.

The metropolitan area of the city of Moscow, the capital of Russia, is almost four times the size of the metropolitan area of the next largest city, Saint Petersburg, and plays a unique and uncontested role of the cultural and political center of the country. It can therefore be considered a primate city.

Primate cities need not be capital cities: governments may establish a new capital city in an attempt to challenge the primacy of the largest city or provide more balanced growth. For example, in Tanzania, Dar es Salaam is still the primate city even though the capital was moved to Dodoma, a new city built to a plan, in 1996. A similar process (though without building a planned city) occurred when the existing city of Wellington was chosen as New Zealand's capital in 1865; Auckland had been the capital, and commanded a greater share of the population and economy.

Asia
For the Philippines, figures are for Metro Manila and Metro Cebu. Manila is the national capital, which is within Metro Manila, a region. Meanwhile, Cebu City is the capital city of the province of Cebu, with Metro Cebu being its main urban center. Metro Manila is within Mega Manila, the megapolis that has a population of around 25 million.

For Malaysia, data for Kuala Lumpur includes the surrounding state of Selangor and the Federal Territory of Putrajaya; while data for George Town includes the entire State of Penang and adjoining regions of Kulim and Kuala Muda (Sungai Petani) in the neighbouring State of Kedah.

Europe
In Germany, Munich (city proper population ca 1.5 million, with surrounding Landkreise ~3 million) is the primate city of the state of Bavaria, having nearly three times the population than the state's second largest, Nuremberg (ca 500,000 people, metro area ~1.35 million). Likewise, in Hesse, Frankfurt (~750,000 people) is nearly three times larger than the state's second largest, Wiesbaden (~275,000) and they are both part of the Rhine-Main metropolitan area, the largest city outside of the area, Kassel, has a population of ca. 200,000 people.

In Italy, primate cities exist at regional level: capital Rome (~2.7 million) alone has nearly half of the population of the Lazio region and is about 21 times larger than the second largest city Latina, and nearly three quarters of the region's population live in the Metropolitan City of Rome Capital. In Lombardy, Milan at ~1.35 million is seven times larger than second largest Brescia (ca 200,000); in Piedmont, Turin has eight-nine times the population of Novara and Alessandria; in Campania, Naples has 7 times the population of second-largest Salerno and in Liguria, Genoa at ~550,000 has six times the population of second largest La Spezia and the Metropolitan City of Genoa has three times the population of Province of Savona.

There are many more regional primate cities in Europe. If excluding national capitals, examples include Gothenburg in Västra Götaland, Sweden, Bergen in Vestland and Trondheim, Trøndelag in Norway, Tampere in Pirkanmaa, Finland and Aarhus in Midtjylland, Denmark.

In Portugal, the Lisbon Metropolitan Area has around 2.8 million people while the Porto Metropolitan Area, the second biggest and other only official metropolitan area, has only around 1.7 million people, these 2 big metropolitan areas have around 40% the country's population and are multiple times larger than the third-biggest city, Braga.

North and Central America
Although Belize does not have a primate city, Belize City is more than twice the size of San Ignacio, the country's second-largest city and urban area. Belize City is also the cultural and economic centre of Belize. The country's capital is Belmopan, the third-largest city in Belize.

In the United States, many primate cities exist at the state level. In California, the population of Los Angeles (~4 million) is nearly three times that of the second-largest city in the state, San Diego. Likewise, in Illinois, Chicago has 15 times the population of the state's second-largest city, Aurora, which itself is a suburb of Chicago, and 18 times the population of Rockford, the state's fifth-largest city and the largest outside of the Chicago metropolitan area, which comprises nearly two-thirds of the state's population. In New York, New York City, with a 2022 population of about 8.3 million, is more than 30 times larger than the state's second-largest city of Buffalo. Erie County, where Buffalo is located, is the eighth-largest county in the state and the largest outside of the New York metropolitan area, with around 950,000 residents; on the other hand, New York City alone contains four of the six largest counties in the state, each with at least 1.35 million residents.

Canada also has several primate cities at the provincial level: Vancouver, BC; Winnipeg, MB; Toronto, ON; Montreal QC; Halifax, NS; and St. John's, NL.

Oceania
Australia does not have a primate city, but at the state level, each of the capital cities of the states and territories act as the primate city of that state or territory.

Partially recognized states
This list only includes cities that the breakaway state controls.