El Salvador's history of political upheaval, rebellion and repression began to pick up a dangerous momentum early in this century. Worker unrest resulted in the creation of a National Guard in 1912, but despite this governmental edict workers' parties only grew in number and strength. It was during this period--ten years after the First World War--that Farabundo Marti formed El Salvador's Communist Party to oppose the ruling oligarchy of foreigners and El Salvadorans willing to aid their interests. In the 50-odd years since then, tension between the workers and the government has increased.

The path to El Salvador's all-out civil war, however, intensified in October 1979 when a group of "progressive" military officers overthrew the rightist military government and formed a coalition with several leftist political parties. The new government, backed by the United States, pledged widespread agrarian reform and aid to the country's six million poor. It also promised to put an end to repression and human rights abuses by the armed forces, and simultaneously to supress the leftist guerrillas they felt were a danger to the state.

Despite the promises, all of the moderate left civilians in the new government resigned four months later, charging the military half of the coalition with continuing repression. This splinter group formed an alliance with the Marxist guerrilla groups organized in the countryside.

Later, the military coalition did hand over the presidency to Antonio Morales Erlich and Jose Napoleon Duarte. They too called for massive land reform and control of the military forces. The United States announced its support for this "reform-minded" coalition.

But opponents say the new government is as repressive as the old, frequently noting that political murders in 1980 skyrocketed to more than 10,000.

El Salvador's greatest political crisis struck at the end of November, when six leftist leaders were gunned down in the country's capital, San Salvador. This incident was closely followed by the murder of three American nuns, an event which prompted former president Jimmy Carter to suspend aid to El Salvador. In both cases, rightist military forces and military officials were suspected. The U.S. government initiated an investigation of the nuns' slaying. But despite inconclusive findings and the reported opposition of former Secretary of State Edmund S. Muskie, Carter resumed both economic and military support to Duarte shortly before leaving office.

Leftist guerrillas, fueled by aid from several countries, including Nicaragua, Cuba and Libya, recently started major offensives against the Duarte government, so far with mixed results. In the first stage of the offensive, more than 20,000 government workers walked off their jobs in support, but government forces prevented the guerrillas from capturing hoped-for symbolic military victories before President Reagan's inauguration.

The guerrillas now believe that they can continue their offensive for at least three more months, and government officials say they can retain control, at least over the major cities, with continued U.S. support. Neither side has reported great progress. Anticipating a change in the military and political situation when Reagan, as expected, escalates arms sales to the Duarte government, both sides in the battle await the move from Washington.