Athanassios Nicholas "Thanassi" Yiannopoulos, a former LSU and Tulane University law professor who spent decades revising Louisiana's civil code, died Wednesday at Tulane Hospital. He was 88.

Yiannopoulos, a third-generation lawyer, came to adulthood opposing Fascism and chaos under Nazi occupation in his native Greece, and went on to restore order to Louisiana civil law.

In the March 1999 Tulane Law Review, Judge James L. Dennis wrote that Yiannopoulos played an "essential" role in "a renaissance of the civil law in Louisiana in the 1960s and 1970s."

Yiannopoulos was born in 1928 in Thessaloniki in northern Greece. During World War II, he "suffered the ignominy of Fascist occupation, as well as famine," he told Tyler Storms in a 2016 interview for the Louisiana Bar Journal.

"I was 15 when I joined the youth resistance movement against the Fascists. A German officer caught me painting resistance slogans on a wall in Aristotle Square, in the heart of Thessaloniki. When he attempted to arrest me, I unloaded my entire paint bucket on his face and, of course, ran for dear life!"

After the war, he earned a law degree from the University of Thessaloniki in 1950, but his career was interrupted when he was called to serve in the military. During his service in Athens, he won a Fulbright Fellowship; three days after his discharge, he was on a boat to New York.

"After the hardships of war and reconstruction, life in the USA was a dream," he told Storms. In the United States, he earned advanced law degrees from the University of Chicago and the University of California, Berkeley.

He was teaching law at the University of Cologne in Germany when Dean William Prosser of the Berkeley law school recommended him for a job as an associate professor of law at LSU, which he accepted in 1958.

"Thanassi had a million friends," said Jerry Dodson, a friend and colleague who met Yiannopoulos as a student in one of his LSU classes.

Yiannopoulos returned to Greece for a brief, disappointing stint in 1968 but returned the next year to LSU, where he began the work of revising the Louisiana civil code that was to dominate the rest of his career.

Louisiana operates on a civil law system, with its roots in France, Spain and ultimately ancient Rome. The other 49 states operate on the English common law system. Civil law places greater emphasis on the content of legislation and less emphasis on judicial interpretation and precedent.

However, the civil code had lost much of its relevance and usefulness by the time Yiannopoulos arrived at LSU. Louisiana legal tradition had been distorted by the influence of the English common law in the other 49 states.

Fundamental differences between civil law and common law produced a civil code that "seemed irrelevant, out of touch with reality and suspended in a vacuum," Yiannopoulos told Storms.

“Anglo-American legal tradition looks first to the judge-made law. In Louisiana, and thanks to Yiannopoulos, the civil code is again the primary source of law,” said Storms, whose interview with Yiannopoulos appeared in the 75th anniversary issue of the Louisiana Bar Journal, which declared Yiannopoulos “Louisiana’s most influential jurist in our time.”

"He's one of the true giants of the Louisiana civil law," said Jack Weiss, chancellor emeritus of the LSU law school. "His teaching and scholarship have shaped Louisiana civil law for multiple generations of lawyers and judges. "

In 1979, Yiannopoulos accepted a position with the Tulane Law School, where he was a professor until 2007. He was the lead teacher for a civil law seminar until 2015. He began directing the school's summer program in Greece in 1980, teaching maritime law, in which he was also expert.

U.S. District Judge John DeGravelles of Baton Rouge said Yiannopoulos cherished his Greek heritage, ever eager to talk about classical archaeology and "remind us all what percentage of the words in English have their origins in the Greek language."

Months before his death, he was still at work, anticipating publication of a volume of expert commentary on the civil code in July.

Survivors include his wife, Mirta; his children, Maria, Nicholas, Alexander and Philip Yiannopoulos; a sister, Aspasia Sougaria; and several grandchildren.

Plans for a memorial service are incomplete.