Battle of the Paracel Islands

The Battle of the Paracel Islands was a military engagement between the naval forces of China and South Vietnam in the Paracel Islands on January 19, 1974. The battle was an attempt by the South Vietnamese navy to expel the Chinese navy from the vicinity.
As a result of the battle, the PRC established "de facto" control over the Paracels.
Background.
The Paracel Islands, called Xisha Islands (; "Xīshā Qúndǎo") in Chinese and Hoang Sa Islands ("Quần Đảo Hoàng Sa") in Vietnamese, lie in the South China Sea approximately equidistant from the coastlines of the PRC and Vietnam (200 nautical miles). With no native population, the archipelago’s ownership has been in dispute since the early 20th century.
China first asserted sovereignty in the modern sense to the South China Sea’s islands when it formally objected to France’s efforts to incorporate them into French Indochina during the Sino-French War (1884–1885). Initially, France recognized Qing China's sovereignty over the Paracel and Spratly archipelagos, in exchange for Chinese recognition of Vietnam as a French territory. Chinese maps since then have consistently shown China’s claims, first as a solid and then as a dashed line. 
In 1932, one year after the Japanese Empire invaded northeast China, France formally claimed both the Paracel and Spratly Islands; China and Japan both protested. In 1933, France bolstered their claim and seized the Paracels and Spratlys, announced their annexation, and formally included them in French Indochina. They built several weather stations on them, but they did not disturb the numerous Chinese fishermen found there. 
In 1938 Japan took the islands from France, garrisoned them, and built a submarine base at Itu Aba (now Taiping / 太平) Island. In 1941, the Japanese Empire made the Paracel and Spratly Islands part of Taiwan, then under its rule.
In 1945, in accordance with the Cairo and Potsdam Declarations and with American help, the armed forces of the Republic of China government at Nanjing accepted the surrender of the Japanese garrisons in Taiwan, including the Paracel and Spratly Islands. Nanjing then declared both archipelagoes to be part of Guangdong Province. In 1946 it established garrisons on both Woody (now Yongxing / 永兴) Island in the Paracels and Taiping Island in the Spratlys. France promptly protested. 
The French tried but failed to dislodge Chinese nationalist troops from Yongxing Island (the only habitable island in the Paracels), and established a small camp on Pattle (now Shanhu / 珊瑚) Island in the southwestern part of the archipelago.
In 1950, after the Chinese nationalists were driven from Hainan by the People’s Liberation Army (PLA), they withdrew their garrisons in both the Paracels and Spratlys to Taiwan. In 1954 France ceased to be a factor when it accepted the independence of both South and North Vietnam and withdrew from Indochina.
In 1956 the PLA reestablished a Chinese garrison on Yongxing Island in the Paracels, while the Republic of China (Taiwan) stationed troops on Taiping Island in the Spratlys. That same year, however, South Vietnam reopened the abandoned French camp on Shanhu Island and announced it had annexed the Paracel archipelago as well as the Spratlys. To focus on its war with the North, South Vietnam by 1966 had reduced its presence on the Paracels to only a single weather observation garrison on Shanhu Island. The PLA made no attempt to remove this force.
Prelude.
On January 16, 1974, six South Vietnamese Army officers and an American observer on the frigate "Lý Thường Kiệt" (HQ-16) were sent to the Paracels on an inspection tour. They discovered two Chinese “armored fishing trawlers” laying off Drummond Island to support a detachment of PLA troops who had occupied the island. Chinese soldiers were also observed around a bunker on nearby Duncan Island, with a landing ship moored on the beach and two additional Kronstadt-class submarine chasers in the vicinity. This was promptly reported to Saigon, and several naval vessels were sent to confront the Chinese ships in the area. 
The South Vietnamese Navy frigate signaled the Chinese squadron to withdraw, and in return received the same demand. The rival forces shadowed each other overnight, but did not engage.
On January 17, about 30 South Vietnamese commandos waded ashore unopposed on Robert Island and removed the Chinese flag they found flying. Later, both sides received reinforcements. The frigate "Trần Khánh Dư" (HQ-4) joined the "Lý Thường Kiệt" (HQ-16), while two PLA Navy minesweepers (#274 and #271) joined the Chinese.
On January 18, the frigate "Trần Bình Trọng" (HQ-5) arrived carrying the commander of the South Vietnamese fleet, Colonel Hà Văn Ngạc. The corvette "Nhật Tảo" (HQ-10) also reached the islands, moving cautiously because it had only one functioning engine at the time.
Balance of forces.
These four warships from the South Vietnam Navy would participate in the battle: the frigates, , , and , and the corvette . A platoon of South Vietnamese naval commandos, an underwater demolition team, and a regular ARVN platoon were by now stationed on the islands.
China also had four warships present: the PLA Navy minesweepers "271", "274", "389" and "396". These were old and small warships with an average length of and width of , and they had not been well-maintained. They were reinforced by two Type 037 submarine chasers ("281" and "282") by the end of the battle. In addition, two PLA marine battalions and an unknown number of irregular militia had been landed on the islands. The 48th Aviation Division of the People's Liberation Army Air Force provided some air support.
Although four ships were engaged on each side, the total displacements and weapons of the South Vietnamese ships were superior. The supporting and reinforcement forces of the PLA Navy did not take part in the battle.
Military engagement.
In the early morning of January 19, 1974, South Vietnamese soldiers from "Trần Bình Trọng" landed on Duncan Island and came under fire from Chinese troops. Three South Vietnamese soldiers were killed and more were wounded. Finding themselves outnumbered, the South Vietnamese ground forces withdrew by landing craft, but their small fleet drew close to the Chinese warships in a tense standoff.
At 10:24 a.m., the South Vietnamese warships "Lý Thường Kiệt" and "Nhật Tảo" opened fire on the Chinese warships. "Trần Bình Trọng" and "Trần Khánh Dư" then joined in. The sea battle lasted about 40 minutes, with vessels on both sides taking damage. The smaller Chinese warships managed to maneuver into the blind spots of the main cannons on the South Vietnamese warships and damaged all four South Vietnamese ships, especially "Nhật Tảo", which could not retreat because her last working engine was disabled. 
The crew was ordered to abandon ship, but her captain, Lieutenant Commander Ngụy Văn Thà, remained on board and went down with his ship. "Lý Thường Kiệt", severely damaged by friendly fire from "Trần Bình Trọng", was forced to retreat westwards. "Trần Khánh Dư" and "Trần Bình Trọng" soon joined in the retreat.
The next day, Chinese aircraft from Hainan bombed the three islands, and an amphibious landing was made. The outnumbered South Vietnamese marine garrison on the islands was forced to surrender, and the damaged navy ships retreated to Đà Nẵng.
During the battle, the South Vietnamese fleet detected two more Chinese warships rushing to the area. China later acknowledged these were the Hainan-class submarine chasers "281" and "282". Despite South Vietnamese reports that at least one of their ships had been struck by a missile, the Chinese insisted what the South Vietnamese saw were rocket-propelled grenades fired by the crew of #389 and that no missile-capable ships were present, and the Chinese ships closed in because they had no missiles. The South Vietnamese fleet also received warnings that U.S. Navy radar had detected additional Chinese guided missile frigates and aircraft on their way from Hainan.
South Vietnam requested assistance from the U.S. Seventh Fleet, but the request was denied.
Result.
Following the battle, China gained control over all of the Paracel Islands. South Vietnam protested to the United Nations, but China, having veto power on the UN Security Council, blocked any efforts to bring it up. The remote islands had little value militarily, but diplomatically the projection of power was beneficial to China.
South Vietnamese casualties.
The South Vietnamese reported that the warship "Nhật Tảo" was sunk and "Lý Thường Kiệt" heavily damaged, while "Trần Khánh Dư" and "Trần Bình Trọng" were both slightly damaged. 53 South Vietnamese soldiers, including Captain Ngụy Văn Thà of "Nhật Tảo", were killed, and 16 were wounded. On January 20, 1974, the Dutch tanker, "Kopionella", found and rescued 23 survivors of the sunken "Nhật Tảo". On January 29, 1974, South Vietnamese fishermen found 15 South Vietnamese soldiers near Mũi Yến (Qui Nhơn) who had fought on Quang Hòa island and escaped in lifeboats.
After their successful amphibious assault on January 20, the Chinese held 48 prisoners, including an American advisor. They were later released in Hong Kong through the Red Cross.
Chinese casualties.
The Chinese claimed that even though its ships had all been hit numerous times, none of them had been sunk. Warships "271" and "396" suffered speed-reducing damage to their engines, but both returned to port safely and were repaired. "274" was damaged more extensively and had to stop at Yongxing Island for emergency repairs. It returned to Hainan under its own power the next day.
"389" was damaged the most by an engine room explosion. Its captain managed to run his ship aground and put out the fire with the help of the minesweepers. It was then towed back to base. Eighteen Chinese sailors were killed and 67 were wounded in the battle.
Aftermath.
A potential diplomatic crisis was averted when China released the American prisoner taken during the battle. Gerald Emil Kosh, 27, a former U.S. Army captain, was captured with the South Vietnamese on Pattle Island. He was described as a “regional liaison officer” for the American embassy in Saigon on assignment with the South Vietnamese Navy. China released him from custody on January 31 without comment.
The leaders of North Vietnam gave a glimpse of their worsening relationship with China by conspicuously not congratulating their ally. An official communique issued by the Provisional Revolutionary Government of the Republic of South Vietnam mentioned only its desire for a peaceful and negotiated resolution for any local territorial dispute. In the wake of the battle, North Vietnamese Deputy Foreign Minister Nguyễn Cơ Thạch told the Hungarian ambassador to Hanoi that "there are many documents and data on Vietnam's archipelago." Other North Vietnamese cadres told the Hungarian diplomats that in their view, the conflict between China and the Saigon regime was but a temporary one. However, they later said the issue would be a problem of the entire Vietnamese nation.
After the reunification of Vietnam in April 1975, the Socialist Republic of Vietnam publicly renewed its claim to the Paracels, and the dispute continues to this day. Hanoi has praised the South Vietnamese forces that took part in the battle.