Monday's expected bankruptcy filing by General Motors Corp. (GM) caps a dramatic series of events in the past year that have reshaped the American car industry and its relationship with the U.S. government.

GM had struggled financially for years due largely to high labor costs and increased competition from foreign car companies. But auto industry observers point to several factors to emerge since last summer that pushed GM to the brink of collapse: a devastating spike in gas prices, the freezing of credit markets and the deterioration of the broader economy.

At the same time, the U.S. government took unprecedented steps to keep GM afloat. It gave the company $19.4 billion in taxpayer money, ousted its chief executive and became the direct overseer of its restructuring. Washington's role is set to become even broader in bankruptcy. The U.S. government will provide $30.1 billion in financing for GM to restructure and will hold a 60% majority ownership stake. Canada will provide $9.5 billion and will receive approximately $1.7 billion in debt and preferred stock, and approximately 12% of the equity of the new GM.

Signs of the depths of GM's financial troubles began to emerge last summer. By July, the price of a gallon of gasoline had reached $4, and a dramatic shift in consumer behavior had taken hold, with consumers turning more toward fuel-efficient cars than SUVs and trucks.

That scenario particularly spelled trouble for Detroit's Big Three - GM, Chrysler, and Ford Motor Co. - who long ago made SUVs and light trucks the linchpin of their product lines.

The growing financial crisis further cut into car sales, as consumers pulled back spending and found it increasingly difficult to qualify for car loans. The companies themselves also found it nearly impossible to borrow money at reasonable prices on the open market, and by late summer, there was talk that GM and Chrysler, who had started to burn rapidly through their cash reserves, would need some kind of handout from the government.

The situation worsened in the fall. Sales dipped even further as rising unemployment and other problems associated with the economic recession caused more and more consumers to put off car purchases. By February, the seasonally adjusted rate for new cars and light trucks fell to 9.12 million, far off from the 15.4 million vehicle pace a year earlier.

David E. Cole, chairman of the Center for Automotive Research in Ann Arbor, Mich., said the spike in gas prices played a role in the auto makers' rapid decline, but that the credit freeze and recession were far bigger factors. "That was the 500-pound gorilla," he said.

By November, the former titans of American manufacturing had been brought to their knees, with their CEOs appearing before Congress begging for aid.

A little over a month later, after Congress failed to pass a bailout bill, President George W. Bush's administration relented and sent GM and Chrysler a lifeline using money from the banking-rescue program, convinced that a collapse of one of the auto makers would be catastrophic. President Barack Obama, shortly after taking office, created an auto industry task force and eventually set a June 1 deadline for GM to submit a viability plan or enter into bankruptcy proceedings.

Josh Mitchell, Dow Jones Newswires, (202) 862-6637, joshua.mitchell@dowjones.com