The name Luzon is thought to derive from ᜎᜓᜐᜓᜅ᜔ lusong, a Tagalog word referring to a particular kind of large wooden mortar used in dehusking rice. A 2008 research paper by Eulito Bautista and Evelyn Javier provides an image of a lusong, explaining:

Traditional milling was accomplished in the 1900s by pounding the palay with a wooden pestle in a stone or wooden mortar called lusong. The first pounding takes off the hull and further pounding removes the bran but also breaks most grains. Further winnowing with a bamboo tray (bilao) separates the hull from the rice grains. This traditional hand-pounding chore, although very laborious and resulted in a lot of broken rice, required two to three skilled men and women to work harmoniously and was actually a form of socializing among young folks in the villages.

In old Latin, Italian, and Portuguese maps, the island is often called Luçonia or Luconia.

Luções, [luˈsõjʃ] (also Luzones in Spanish) was a demonym used by Portuguese sailors in Malaysia during the early 1500s, referring to the Kapampangan and Tagalog people who lived in Manila Bay, which was then called Lusong (Kapampangan: Lusung, Portuguese: Luçon), from which Luzon was also derived. The term was also used for Tagalog settlers in Southern Tagalog region, where they created intensive contact with the Kapampangans. Eventually, the term "Luzones" would refer to the settlers of Luzon island, and later on, would be exclusive to the peoples of Central Luzon.

Before 1000 CE, the Tagalog, Kapampangan, and Pangasinan peoples of south and central Luzon had established several major coastal polities, notably Maynila, Tondo and Namayan. The oldest known Philippine document, written in 900, is the Laguna Copperplate Inscription, which names places in and around Manila Bay and also mentions Medan, a place in Indonesia. These coastal Philippine kingdoms were thalassocracies, based on trade with neighboring Asian political entities, and structured by leases between chiefs or lords (Datu) and paramount lords (Lakan) or Rajahs, by whom tributes were extracted and taxes were levied.

There was also a Buddhist polity known as Ma-i or Maidh, described in Chinese and Bruneian records in the 10th century, although its location is still unknown and scholars are divided on whether it is in modern-day Bay, Laguna or Bulalacao, Mindoro.

According to sources at the time, the trade in large native Ruson-tsukuri (literally Luzon-made, Japanese:呂宋製) clay jars used for storing green tea and rice wine with Japan flourished in the 12th century, and local Tagalog, Kapampangan and Pangasinan potters had marked each jar with Baybayin letters denoting the particular urn used and the kiln the jars were manufactured in. Certain kilns were renowned over others; prices depended on the reputation of the kiln. Of this flourishing trade, the Burnay jars of Ilocos are the only large clay jar manufactured in Luzon today with origins from this time.

In the early 1300s the Chinese annals, Nanhai zhi, reported that Hindu Brunei invaded or administered Sarawak and Sabah as well as the Philippine kingdoms of Butuan, Sulu, and in Luzon: Ma-i (Mindoro) and Malilu 麻裏蘆 (present-day Manila); Shahuchong 沙胡重 (present-day Siocon or Zamboanga), Yachen 啞陳 Oton (Part of the Madja-as Kedatuan), and 文杜陵 Wenduling (present-day Mindanao), which would regain their independence at a later date.

In 1405, the Yongle Emperor appointed a Chinese governor of Luzon, Ko Ch'a-lao, during Zheng He's voyages. China also had vassals among the leaders in the archipelago. China attained ascendancy in trade with the area in Yongle's reign.

Afterwards, some parts of Luzon were Islamized when the former Majapahit province of Poni broke free, converted to Islam, and imported Sharif Ali, a prince from Mecca who became the Sultan of Brunei, a nation that then expanded its realms from Borneo to the Philippines and set up the Kingdom of Maynila as its puppet-state. The invasion of Brunei spread Chinese royal descent like Ong Sum Ping's kin and Arab dynasties too into t…

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As of the 2015 census, the population of Luzon Island is 57,470,097 people, making it the 4th most populated island in the world.
Metro Manila is the most populous of the 3 defined metropolitan areas in the Philippines and the 11th most populous in the world. as of 2007 , census data showed it had a population of 11,553,427, comprising 13% of the national population. Including suburbs in the adjacent provinces (Bulacan, Cavite, Laguna, and Rizal) of Greater Manila, the population is around 21 million.
Seven major Philippine ethnolinguistic groups predominate Luzon. Ilocanos and Pangasinenses dominate northern Luzon, particularly in the Ilocos Region to parts of the Cagayan Valley, while Kapampangans, Tagalogs, Ilocanos, and Sambals populate Central Luzon. Tagalogs dominate the National Capital Region, Calabarzon and the island provinces of Marinduque, Mindoro and extending to parts of Palawan and northern Bicol Peninsula, while Bicolanos populate the Bicol peninsula. Visayans, such as Masbateños, Romblomanons, Waray Sorsogonons, Cuyunons, mainly populate in the southern Bicol peninsula and island provinces of Masbate, Romblon, and Palawan.

Other ethnic groups lesser in population include the Aetas of Zambales and Bataan, the Ibanags of Cagayan and Isabela, the Gaddang of Nueva Vizcaya, the Igorot of the Cordilleras, and the Mangyans of Mindoro.

Due to historical centuries-old migrations, populations of ethnic Chinese Filipinos, Spanish Filipinos, Japanese Filipinos, Indian Filipinos, and Muslim Moros from Mindanao have also been present in urban areas. Historical mixed mestizo populations, particularly Chinese mestizos (mestizo de Sangley) and Spanish mestizos, and more recent mixed mesitzos of Americans, Japanese, Koreans, Indians (mostly Punjabis), and Arabs are also occasionally present. The historical Sangley Chinese and their pure and mixed-mestizo descendants are spread all across Luzon of several generations across the centuries. According to old Spanish censuses, around 1/3rd of the population of Luzon are mestizo admixed with either or both Southern Han Chinese (mostly from Manila to Pampanga) and/or Hispanic (Spanish or Latino) descent (Mostly in Cavite and Manila). Most Americans have settled in Central Luzon's highly urbanized cities of Angeles and Olongapo due to the former presence of the U.S. air and naval bases (Clark & Subic) there, while a majority of the Koreans and Japanese have mainly settled in the major cities and towns like Koreatown in Angeles City and Baguio and Subic.
Almost all of the languages of Luzon belong to the Philippine group of the Malayo-Polynesian branch of the Austronesian language family. Major regional languages include: Tagalog, Ilocano, Central Bikol, Kapampangan, and Pangasinan.

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