In the black of night inside the ornate state guest house where China houses foreign leaders, Gordon Houlden passed the time on an unusual graveyard shift. Not far away, Pierre Trudeau was supposed to be asleep, getting some rest on a quick working visit to Beijing. It was 1983 and Mr. Houlden was then a junior Canadian diplomatic officer, tasked with staying close in case Ottawa called.
Some time after midnight, however, a jet-lagged Mr. Trudeau himself shuffled in. For more than an hour, he peppered Mr. Houlden with questions about China's economy, history, politics and society.
"He had a deep fascination. He was interested in what made the country work and he was prepared to listen," said Mr. Houlden, now director of the China Institute at the University of Alberta.
To Mr. Houlden, it exemplified the Trudeau approach to China: curious, open-minded and rooted in a desire to understand the country. It was an approach that won Mr. Trudeau criticism at home, but favour in China.
Now as Justin Trudeau leaves Canada for his own first visit to China as Prime Minister, shadows of his father will occupy every room he enters, as his hosts see in him a chance to revive the collegiality they once enjoyed.
Pierre Trudeau's affection for the country was great enough that, as Prime Minister, he tried to organize a canoe trip down the Yangtze, although China wouldn't allow it.
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The elder "Trudeau didn't allow much politics to colour Canada-China relations. He took politics out of economic and trade relations," said Tang Xiaosong, executive deputy director of the Centre for Canadian Studies at the Guangzhou Institute of Foreign Languages. "The younger Trudeau, I think, will very much follow in the footsteps of his father. Because his father had a very positive stance toward China."
The elder Trudeau's approach – and appeal – was cemented in 1973, on his landmark visit to Beijing to commemorate the renewal of diplomatic relations between the two countries. After a two-hour meeting with Mao Zedong that followed nearly 11 hours of formal talks with Premier Zhou Enlai, Mr. Trudeau offered flattery for his hosts, speaking of their genius in creating a system "that, in comparison with all previous Chinese social systems, is striving to provide human dignity and equality of opportunity for the Chinese people."
Justin Trudeau was not yet two years old when his father made those comments, which were controversial at the time, when some Canadians sent letters addressed to the "Communist" in Ottawa, and remain so today.
It's not clear how much Mr. Trudeau hews to his father's thinking. Though the younger Trudeau once expressed admiration for the brutal efficiency of China's "basic dictatorship," he has also said Canada will be cautious about deepening its trading relationship with China, citing "an awful lot of work to do" on human rights and governance issues.
Still, China greeted Mr. Trudeau's election last year with talk of a new "golden era" with Canada. The Communist Party-run Global Times, in a Monday editorial, expressed hope the Prime Minister would follow his father's lead. "Junior Trudeau has obviously been influenced by his family's political opinions," it wrote.
On Chinese social media, too, people have connected the two prime ministers. Justin Trudeau has "not only taken up his father's wisdom, but also his mother's looks," wrote one poster.
Pierre Trudeau first came to China in 1949 and returned in 1960, at the invitation of the Chinese government, for a month-long tour he and co-author Jacques Hébert recounted in a book, Two Innocents in Red China, that was once required reading for Chinese diplomats ahead of Pierre Trudeau visits.
The duo describe visits to a Railway Ministry sleeping-car factory and an agricultural commune. At the latter, they watched people smelting pig iron to fashion agricultural implements. What they had witnessed was perhaps the most grievous chapter of Communist Party history, the Great Leap Forward, which forced farmers to produce steel rather than tend crops, resulting in a famine that killed tens of millions.
What Mr. Trudeau and Mr. Hébert concluded, though, was: "We are convinced that we are witnessing the beginning of an industrial revolution."
Mr. Trudeau's equanimity toward China continued long after his time in office. He and his three sons continued to discuss a trip planned for the summer of 1989 even after the massacre around Tiananmen Square. It was only after Canadian officials asked them to cancel that they postponed until the following year.
When they arrived, Alexandre Trudeau, the second-born son, noted "something puzzling about my father's attitude toward China," according to an essay he published in the introduction to a reprint of Two Innocents. In China, Pierre Trudeau barely mentioned the events at Tiananmen, saying instead, "It is hard to know how China needs to move forward. … Missteps in this immense country lead to death and suffering on a gargantuan scale."
Grappling with this, Alexandre saw humility.
"In allowing the Chinese government the mistake of Tiananmen, he was accepting his own inability to change the course of things." His father "had been forced to recognize China as a great nation. China must not be sermonized."
That's a far cry from modern expectations for Canadian political leaders to speak out against China's human-rights abuses, which include torture of dissidents and campaigns to silence lawyers, minorities and other activists.
Long-time diplomats nonetheless say Mr. Trudeau's approach helped foment change. Kick-starting diplomacy with Communist Beijing "was really an inspired move" that helped open China to the West and gave support to those in China who opposed extreme Maoists, said John Higginbotham, a diplomat stationed in Beijing in 1973. Though he gives most of the credit to Mr. Zhou, the Chinese Premier, "I don't think Pierre Trudeau was naive in the slightest. I think he helped change the future of China by supporting the moderate faction," he said.
"It got China off its revolutionary track, both internally and externally. It was a real turning point."
How much should that inform Justin Trudeau today? Both China and Canada are much changed, after all, and the thrill of new diplomacy four decades ago has given way to complex trade and consular matters in an $85-billion relationship.
Still, Mr. Trudeau may be able to profit from the goodwill that has lingered long after his father left office.
Phil Calvert, a recently retired Canadian ambassador who was a junior officer in Beijing in the 1980s, recalled a private trip the elder Trudeau took to China two years after his retirement – and just two weeks before Brian Mulroney arrived in town. It was awkward.
"During receptions for the Trudeau visit, Chinese officials kept saying, 'We are so happy your Prime Minister is in town. Who is the guy coming in two weeks?'"