Anastasio Somoza DeBayle, nicknamed "Tachito" (Spanish: Little Tacho) by his father, was the third child of Anastasio Somoza García and Salvadora DeBayle. At the age of seven, he was enrolled at the Instituto Pedagógico La Salle, run by the Christian Brothers. One of his classmates was Pedro Joaquín Chamorro Cardenal, who would grow up to become one of the most prominent opponents of the Somoza dynasty. From the age of ten, Tachito was educated in the United States. He and older brother Luis Somoza Debayle, both attended St. Leo College Prep (Florida) and La Salle Military Academy (Long Island). He passed the examination for West Point, entered the United States Military Academy on July 3, 1943, and graduated on June 6, 1946.
Two years after his return from West Point, Somoza fathered a daughter, Patricia, who was later sent to a series of schools abroad. Also after his return, he was appointed chief of staff of the National Guard, (Nicaragua's national army), by his father, who had previously given many important posts to family members and close personal friends. As commander of the Guard, Somoza was head of the nation's armed forces, effectively the second-most powerful man in Nicaragua.
On 10 December 1950, Somoza and Hope Portocarrero, an American citizen and his first cousin, were married at the Cathedral in Managua by Archbishop Jose Antonio Lezcano. Over 4,000 guests attended the ceremony. The reception was given by Somoza's father, President Anastasio Somoza García, in the luxurious and modern Palacio de Comunicaciones. Following his father's assassination on 21 September 1956, Somoza's elder brother, Luis, took over the presidency. Anastasio had a large hand in the government during this time, and saw to it that the presidency was held by politicians loyal to his family from 1963 to 1967.
On 1 May 1967, shortly before the death of his brother, Anastasio Somoza was sworn into office following his election on 5 February. While Luis had ruled more gently than his father had, Anastasio would not tolerate opposition of any sort, and his regime soon resembled his father's in all significant respects.
With regard to educating the workforce, Somoza replied, “I don’t want an educated population; I want oxen.”
His term in office was due to end in May 1972, due to a law which disallowed immediate re-election. However, prior to that, Somoza worked out an agreement allowing him to stand for re-election in 1974; he would be replaced as president by a three-man junta consisting of two Liberals and one Conservative while he retained control of the National Guard. Somoza and his triumvirate drew up a new constitution that was ratified by the triumvirate and the cabinet on April 3, 1971. He then stepped down as president on May 1, 1972. However, as head of the National Guard, he remained the de facto ruler of the country.
Anastasio Somoza and his son were both part owners of Plasmaferesis. The company collected blood plasma from up to 1,000 of Nicaragua's poorest every day for sale in the United States and Europe. According to El Diario Nuevo and La Prensa, “Every morning the homeless, drunks, and poor people went to sell half a liter of blood for 35 (Nicaraguan) cordobas.
On 23 December 1972, an earthquake struck the nation's capital, Managua, killing about 5,000 people and virtually destroying the city. Martial law was declared, making Somoza the country's ruler in name as well as in fact once again. He then took over effective control as head of the National Emergency Committee. He reportedly embezzled many of the funds sent from across the world to help rebuild Managua. Some parts of Managua have still never been rebuilt or restored, including the National Cathedral. Somoza also allegedly exported freshly imported emergency blood plasma abroad, at the time of the earthquake, when most medical supplies in Nicaragua were desperately in short supply.
Somoza was re-elected president in the 1974 election. By this time, the Catholic Church had begun to speak against his government (indeed, one of his fiercest critics was Ernesto Cardenal, a leftist Nicaraguan priest who preached liberation theology and would become the Sandinista government's Minister of Culture). By the late 1970s, human rights groups were condemning the record of the Somoza government, while support for the Sandinistas was growing inside and outside the country.
In July 1977, Somoza had a heart attack, and went to the US to recuperate.
In 1975 Somoza Debayle launched a campaign to crush the Sandinistas; individuals suspected of supporting the Front were targeted. The Front, named after Augusto César Sandino (a Nicaraguan rebel leader in the 1920s), began its guerrilla war against the Somozas in 1963 and was funded by the Soviet Union and Cuba under Fidel Castro. Support for the Sandinistas ballooned after the earthquake, especially when U.S President Jimmy Carter withdrew American support for the regime for human rights reasons.
At this point, the opposition to the Somozas included not only Sandinistas, but other prominent figures such as Pedro Chamorro (assassinated on January 10, 1978). Israel was the last supplier of weapons to the Somoza regime, because during the 1947–1949 Palestine war in 1948, Somoza's father provided substantial financial support for Israel. Carter forced the Israeli government to call back a ship carrying weapons vital to the survival of the Somoza regime.
Because of his status, most of his family members were forced to flee into Honduras, Guatemala, and the United States. It is uncertain where the remaining Somozas live given the fact that they changed their names to protect their own lives.
On July 17, 1979, Somoza resigned the presidency and fled to Miami in a converted Curtiss C-46. He took with him the caskets of his father and brother and, it is claimed, much of Nicaragua's national treasure leaving the country with, it is claimed, a $1.6 billion foreign debt, the highest in Central America. After Somoza had fled, the Sandinistas found, it is claimed, less than $2 million in the national treasury.
Somoza was denied entry to the U.S. by President Carter. He later took refuge in Paraguay, then under the dictatorship of Alfredo Stroessner. He bought a ranch and a gated house at Avenida de España no. 433 in Asunción. Somoza's regime lasted only another day, when his successor peacefully handed Managua to the Sandinistas.
Somoza was assassinated near his exile home on September 17, 1980. He was 54 years old. Somoza Debayle was ambushed by a seven-person Sandinista commando team (four men and three women). This was known as "Operation Reptile".