Kyushu in the context of "Satsuma Domain"

Japan is often divided into regions, each containing one or more of the country's 47 prefectures at large. Sometimes, they are referred to as "blocs" (ブロック, burokku), or "regional blocs" (地域ブロック, chiiki burokku) as opposed to more granular regional divisions. They are not official administrative units, though they have been used by government officials for statistical and other purposes since 1905. They are widely used in, for example, maps, geography textbooks, and weather reports, and many businesses and institutions use their home regions in their names as well, for example Kyushu National Museum, Kinki Nippon Railway, Chūgoku Bank, and Tōhoku University.

One common division groups the prefectures into eight regions. In this arrangement, of the four main islands of Japan, Hokkaidō, Honshu, Shikoku, and Kyūshū, each form their own region, with Kyūshū also including the Satsunan Islands. The largest island, Honshū, is split into five regions. Okinawa Prefecture is usually considered part of Kyūshū, but it is sometimes treated as its own ninth region.

Japan is an archipelagic country comprising a stratovolcanic archipelago over 3,000 km (1,900 mi) along the Pacific coast of East Asia. It consists of 14,125 islands. The five main islands are Hokkaido, Honshu, Kyushu, Shikoku, and Okinawa. The other 14,120 islands are classified as "remote islands" by the Japanese government. The Ryukyu Islands and Nanpō Islands are south and east of the main islands.

The territory covers 377,973.89 km (145,936.53 sq mi). It is the fourth-largest island country in the world and the largest island country in East Asia. The country has the 6th longest coastline at 29,751 km (18,486 mi) and the 8th largest Exclusive Economic Zone of 4,470,000 km (1,730,000 sq mi) in the world.

Okinawa Island (Japanese: 沖縄島, Hepburn: Okinawa-jima; Okinawan: 沖縄 / うちなー, romanized: Uchinā; Kunigami: ふちなー, romanized: Fuchináa), also known as Okinawa Main Island (沖縄本島, Okinawa-hontō), is the largest of the Okinawa Islands and the Ryukyu (Nansei) Islands of Japan in the Kyushu region. It is the smallest and least populated of the five main islands of Japan. The island is approximately 106 kilometres (66 mi) long, an average 11 kilometres (7 mi) wide, and has an area of 1,206.98 square kilometers (466.02 sq mi). It is roughly 640 kilometres (350 nmi; 400 mi) south of the main island of Kyushu and the rest of Japan. It is 500 km (270 nmi; 310 mi) northeast of Taiwan. The total population of Okinawa Island was 1,384,762 in 2009. The greater Naha area has roughly 800,000 residents, while the city itself has about 320,000 people. Naha is the seat of Okinawa Prefecture on the southwestern part of Okinawa Island. Okinawa has a humid subtropical climate.

Okinawa has been a strategic location for the United States Armed Forces since the Battle of Okinawa and the end of World War II. The island was formally controlled by the United States Civil Administration of the Ryukyu Islands until 1972, with around 26,000 U.S. military personnel stationed on Okinawa today, comprising about half of the total complement of the United States Forces Japan, spread among 31 areas, across 13 bases and 48 training sites. United States military installations cover approximately 25% of the island and have been a point of contention among locals. Crimes committed by US military personnel, notably the 1995 Okinawa rape incident, have caused protests against the US military presence in Okinawa.

The Ryukyu Islands (Japanese: 琉球列島, Hepburn: Ryūkyū Rettō), also known as the Nansei Islands (南西諸島, Nansei Shotō; lit. 'Southwest Islands') or the Ryukyu Arc (琉球弧, Ryūkyū-ko), are a chain of Japanese islands that stretch southwest from Kyushu to Taiwan: the Ryukyu Islands are divided into the Satsunan Islands (Ōsumi, Tokara and Amami) and Okinawa Prefecture (Daitō, Miyako, Yaeyama, Senkaku, Okinawa, Sakishima Islands (further divided into the Miyako and Yaeyama Islands), and Yonaguni as the westernmost). The larger ones are mostly volcanic islands and the smaller mostly coral. The largest is Okinawa Island.

The climate of the islands ranges from humid subtropical climate (Köppen climate classification Cfa) in the north to tropical rainforest climate (Köppen climate classification Af) in the south. Precipitation is very high and is affected by the rainy season and typhoons. Except the outlying Daitō Islands, the island chain has two major geologic boundaries, the Tokara Strait (between the Tokara and Amami Islands) and the Kerama Gap (between the Okinawa and Miyako Islands). The islands beyond the Tokara Strait are characterized by their coral reefs.

Shikoku (四国, Shikoku; pronounced [ɕi̥ꜜ.ko.kɯ, ɕi̥.koꜜ.kɯ] , lit. 'four provinces') is the smallest of the four main islands of Japan. It is 225 kilometres (140 miles) long and between 50 and 150 kilometres (30 and 95 miles) wide. It has a population of 3.8 million, the least populated of Japan's four main islands. It is south of Honshu and northeast of Kyushu. Shikoku's ancient names include Iyo-no-futana-shima (伊予之二名島), Iyo-shima (伊予島), and Futana-shima (二名島), and its current name refers to the four former provinces that make up the island: Awa, Tosa, Sanuki, and Iyo.

Okinawa Prefecture (Japanese: 沖縄県, Hepburn: Okinawa-ken; pronounced [o.kʲi.na.wa(ꜜ.keɴ)]; Okinawan: 沖縄県, romanized: Uchinaachin) is the southernmost and westernmost prefecture of Japan. It consists of three main island groups—the Okinawa Islands, the Sakishima Islands, and the Daitō Islands—spread across a maritime zone approximately 1,000 kilometers east to west and 400 kilometers north to south. Despite a modest land area of 2,281 km (880 sq mi), Okinawa's territorial extent over surrounding seas makes its total area nearly half the combined size of Honshu, Shikoku, and Kyushu. Of its 160 islands, 49 are inhabited. The largest and most populous island is Okinawa Island, which hosts the capital city, Naha, as well as major urban centers such as Okinawa, Uruma, and Urasoe. The prefecture has a subtropical climate, characterized by warm temperatures and high rainfall throughout the year. People from the Nansei Islands, including Okinawa, the Sakishima Islands, and parts of Kagoshima Prefecture, are often collectively referred to as Ryukyuans. However, there are significant cultural and customary differences between individual islands and even between local communities.

Historically the center of the Ryukyu Kingdom, Okinawa long served as a maritime trading hub and cultural gateway; the kingdom participated in the Chinese tributary system—maintaining formal tribute relations with the Ming and Qing—and retained distinct statehood until it was incorporated into Japan as Okinawa Prefecture in 1879 following the Ryukyu Disposition. After the Battle of Okinawa (1945), the islands were under U.S. administration until reversion to Japan in 1972, and today host a large share of U.S. military facilities in Japan (around 70% by area of land exclusively used by U.S. forces), a continuing source of local and national debate. A small but persistent independence movement exists, reflecting Okinawa's distinct historical trajectory and identity.

Nagasaki (長崎, Nagasaki; Japanese pronunciation: [na.ɡaꜜ.sa.kʲi, na.ŋa-], lit. 'Long Cape'), officially Nagasaki City (長崎市, Nagasaki-shi; [na.ɡa.sa.kʲi̥ꜜ.ɕi, na.ɡa.saꜜ.kʲi̥.ɕi, na.ŋa-]), is the capital and the largest city of Nagasaki Prefecture on the island of Kyushu in Japan.

Founded by the Portuguese, the port of Nagasaki became the sole port used for trade with the Portuguese and Dutch during the 16th through 19th centuries. The Hidden Christian Sites in the Nagasaki Region have been recognized and included in the UNESCO World Heritage Sites list. Part of Nagasaki was home to a major Imperial Japanese Navy base during the First Sino-Japanese War and Russo-Japanese War. Near the end of World War II, the American atomic bombings of Hiroshima and Nagasaki made Nagasaki the second city in the world to experience a nuclear attack. The city was later rebuilt.

The Ryukyuans are a Japonic-speaking East Asian ethnic group indigenous to the Ryukyu Islands, which stretch from the island of Kyushu to the island of Taiwan. In Japan, most Ryukyuans live in the Okinawa Prefecture or Kagoshima Prefecture. They speak the Ryukyuan languages, one of the branches of the Japonic language family along with the Japanese language and its dialects.

The United Nations Human Rights Committee in 2008 recommended that Japan, "should expressly recognize the Ainu and Ryukyu/Okinawa as indigenous peoples in domestic legislation, adopt special measures to protect, preserve, and promote their cultural heritage and traditional way of life, and recognize their land rights." The Japanese government has not accepted this recommendation because recognizing, "the Ryukyuan as Indigenous Peoples [would require Japan] to adhere to international law, thus prohibiting military bases on [Ryukyuan] land."