The former French president has faced several legal cases since leaving office, but accusations that he received money for his 2007 election from Libyan authorities have been particularly damaging.
Former President Nicolas Sarkozy of France on Monday went on trial in Paris over accusations that his 2007 campaign received illegal financing from the Libyan government of Col. Muammar el-Qaddafi.
The trial, which is scheduled to last three months, is far from the first for Mr. Sarkozy, 69, a conservative politician who led France from 2007 to 2012. But it represents one of the most serious legal threats to the French politician since he left office.
Just last month, Mr. Sarkozy exhausted his final appeal in a separate corruption and influence peddling case, making him the first former French president sentenced to actual detention, though he will serve his time under house arrest with an electronic bracelet.
But of all the legal cases against Mr. Sarkozy, the Libya one is probably the most sprawling, convoluted and explosive. It involves accusations that his campaign illegally accepted significant funding from Colonel Qaddafi, the former Libyan strongman who was killed by opposition fighters in 2011.
Mr. Sarkozy, who no longer holds public office but retains some political influence, has denied wrongdoing but could face up to 10 years in prison and be fined nearly $400,000.
Here is what you need to know about the case.
What is the trial about?
Mr. Sarkozy is facing charges of illegal campaign financing, criminal conspiracy, concealing the misappropriation of public funds and passive corruption (a charge that applies to people suspected of receiving money or favors).